According to Google, speech inputs have grown 6X in the past year, as shown in the graph below. As voice technology continues to improve, voice search is quickly becoming more important in mobile content discovery and site optimization.

Source: http://www.blindfiveyearold.com/search-trends-to-watch-2011

The fanfare associated with Siri, the voice-activated virtual assistant on the most recent iPhone 4s, is the main reason that voice search has more in the spotlight, but voice search has actually existed for a number of years.

Google has offered a speech-input search app since 2009, available for download on iPhone, BlackBerry and Nokia s60. This functionality is also now standard on Android phones, and can be downloaded from the Android Marketplace if it is not already pre-loaded. Before these apps were available, Google even offered Goog411, which was a phone number that searchers could call to submit a search, and have the results read to them or sent directly to their phone via SMS.

Big Strides Have Been Made In Voice Recognition

Historically, the technological interpretation of voice commands has been less than accurate, which made early adoption and enthusiasm for voice search weak. Variations of different languages, dialects, pitches and accents must be cataloged, and understood, even in noisy conditions. It’s not an easy task.

While it was not widely publicized, the voice understanding technology that Google uses is probably relying on the same technologies that drive Google Instant and Google QDF and Google Quality Score, in which cloud-based analysis of a consistently strong CTR  (and low bounce rate) for a lower-ranking site will naturally gain it credibility and rankings over time, as it gets more clicks than the listings above it. This kind of long-term reinforcement with clicks is probably informing and altering voice search results, or it will soon.

Here is what Google is saying about Google’s Voice Search:

“Our goal is to bring Google Search by voice to speakers of all languages. We follow a rigorous process to add each new language or dialect. Working directly with native speakers in each country, we spend weeks collecting spoken utterances to create the specific models which power the service. Our helpers are asked to read popular queries in their native tongue, in a variety of acoustic conditions such as in restaurants, out on busy streets, and inside cars. We also construct, for each language, a vocabulary of over one million recognizable words. It’s no small feat, but we love doing it.”

Similar Queries For Text And Voice Mobile Search

The good news about voice search, in terms of content discovery, is that it appears to simply translate a voice query then submit it thorough the same mobile search algorithms as if it was typed in. This means that there is no algorithmic change, and the only major change for a mobile SEO strategy would be to anticipate the longer and more casual, question-based queries, which are more common in voice search.

Google Mobile Voice-Based Search Categories are Similar to Mobile Text-Based Search Categories

As a whole, voice based search is most common for local searches, but this is likely because most early Android devices included Google Maps with the voice search functionality. Other than that, the categories that are commonly searched for in mobile voice search appear to be very similar to mobile text-based search.

The mobile ad network Chitika reports that the biggest category of voice search is “News” at 20%. After that is “Reference” at 17% then “Other” at 15%, and these are all largely similar to the text-based searches that they measure from in the Google Search Application.

Virtual Assistants Drive Data Usage

Interestingly, access to a virtual assistant like Siri appears to drive lots of engagement with digital information in the form of mobile data. The Huffington Post reports that: “iPhone 4S users transfer on average three times more data than users of the older iPhone 3G model….”

Some of the data consumption can be attributed directly to the heavy requests that come from Siri, as she scours multiple primary sources to get your answers, but another component is the reduced barrier to search. Without having to type, search and access to digital information becomes much easier and more casual.

While Siri has only launched in the US, Apple Insider reports that this will soon change:

‘Siri is still in beta mode, with limited functionality outside of the U.S. Apple is, however planning a rapid international expansion for Siri this year. The company is actively hiring iOS software engineers to help develop the Application Programming Interface for Siri and port the feature to other languages.’

Siri and her other virtual assistant competitors can complete a variety of tasks and access a variety of different information, beyond simply inputting a search query. They can pull information from a number of sources directly and only default to a web search if they do not have access to more specific information.

Create Feeds To Assist Assistants

This adds to the complexity of optimizing for voice search. Beyond anticipating what keywords people will use to search, we are now forced to anticipate what sources the virtual assistant will prefer or recommend. The good news, this may be less of a black box, and more influence-able if someday you are able to work directly with Apple, and submit qualified XML feeds.

All of the sources that Siri pulls data from are just websites that are sending Apple specialized feeds, so that Siri can access the information more quickly.

While it cedes a lot of information and power to Apple, it seems like the biggest win in voice search would be for Apple to work directly mobile resource sites to accept their information feeds. This would mean that users have quicker access to information about show times, character bios, episode summaries, celebrity bios and maybe even movie trailers and music news.

With this strategic move, you would become a primary source of information for your niche, and would not have to rely so heavily on Google to help people find your mobile content.

This article will look at what percent of sites have developed a mobile-specific website experience and how they are presenting the mobile content to their users across different mobile handsets.

Once the Quantcast Top Million US Sites Data from 2011 was made public, a company called Mongoose Metrics created a bot that was meant to crawl all these Top Sites and gather data about how they were serving their mobile content.

While the crawler was intended to answer some very specific questions about how mobilization was achieved on top sites, the data mostly show the dearth of Top Sites that are actively addressing their mobile traffic.

Mongoose Metrics began by testing to see what portion of the Top Million sites were accessible to their crawler, and published a cool mobile marketing study with the results.

In the study they found 15,981 sites, or 1.6% of sites, were blocking crawlers and could not be evaluated and 112,346 or about 11.2% returned errors to the crawler. So the other 87.2% of sites were available to evaluate (great news!)

They made the crawler simulate a site visit as an iPhone, and Android phone and a Blackberry, and the results of those crawls are in the table below:

Mobile Crawl Results By OS - Mobile Publishing

An average of only 7.2% of sites were serving mobilized content. You would think that more marketing departments and CEO’s would demand that they be serving a mobile-specific web experience on their sites, especially since these are the US sites with the ‘top’ traffic in 2011, but, according to this study, that is not the case.

The lack of webmaster attention to mobile traffic could indicate a few different things:

1. Companies are ignoring mobile traffic or assuming that people will be able to successfully use a traditional website on their mobile phone.
2. Decision makers believe that mobile solutions are still too complicated and expensive and are not expected to generate enough revenue to justify the expense.
3. Companies are confused about what their customers want in a mobile experience and don’t know how to address the problem.
4. Companies are providing a mobile-specific experience or a mobile-adapted experience that can’t be detected by the crawlers, such as a Responsive Design approach with flexible layout that adapts itself to mobile phones without changing the page code or redirecting to another page.

So what does all this data mean to you and your company if you are about to launch a mobile marketing campaign? The Mongoose Metrics study that generated those results evaluated three different types of mobile publishing:

1. Server-Side Redirection
2. On-Page JavaScript Redirection
3. Selective Serving of Mobile Content (what they describe as “cloaking.”)

The summarized results of the findings look like this:

Based on the data from the Mongoose Metrics analysis, the most common strategy for mobile publishing is with server-based user-agent detection and redirection. This means that when the desktop pages are requested, the server will automatically send people to the mobile version of the page instead.

The next option, which Mongoose Metrics describes as “cloaking,”’ is the second most popular way to serve mobile pages. I prefer to describe this method as “selective serving” rather than “cloaking” because, for the most part, you are deciding to “send” or “not send” content based on the device that is accessing the page, rather than altering the intent of the page.

To understand how it works, consider this example: If there is a massive image on a page, your server might decide to send a smaller, lower resolution photo when a phone is accessing the site. Similarly, if there is heavy Flash video, your server might decide to send a still picture instead.

If you are using this “cloaking” method of mobile content negotiation,  make sure that you are showing essentially the same content, so that it does not look like it is an attempt to manipulate the search engines (as in the bad sense of the word “cloaking”).

The Bing statement about mobile SEO last month, which followed Google’s announcement about the new smartphone crawler in December, has sparked some discussion, and given mobile SEO some time in the spotlight.

The debate has been interesting, but all of it seems to focus a bit too much on the wrong question. The search engines all emphatically instruct webmasters not to make decisions purely on the SEO implications, but to also consider the user experience.

While I always take this suggestion with a very large and suspicious grain of salt, I do think it is important to consider the users who access the site….as well as the marketing managers who have to promote the mobile content and the developers who maintain the site, (and who will readily tell you that they almost always get the short end of the stick, whether you are talking about mobile design and development, or just about anything else … poor misunderstood souls!).

So let’s discuss the question of mobile site structure from the perspective of an SEO, but also give these other groups a bit more attention.

We can’t forget to consider how users, marketing managers and site development/maintenance teams will be effected by the decision to keep all content on one URL using Responsive Design (the most common way to do it) or the decision to break the content out and have separate mobile pages on a mobile subdomain or subdirectory.

What Do SEOs Want?

First, we’ll discuss the SEO, since it is obviously very important. In the SEO world, we are commonly asked to look at situations are respond with “ideal” solutions that are frequently unachievable without also adding in “ideal” budgets, resources and timelines.

This happens even more commonly in mobile, because of the added complexity in mobile SEO, which pushes the ideal much further away from the “possible.”

There is a lot of debate on this topic, and that is because there is not one perfect answer. The best option will depend on what you already have in place, and what your assets and limitations are for the mobile SEO effort. In my experience and best estimation, most SEOs will have the following thoughts regarding the question of mobile site architecture:

What Do Users Want?

While it might be easy to argue that users would prefer multiple designs, suited for whatever device they happen to be on, it is almost impossible to claim that users would prefer multiple URLs, and keep a straight face.

Except for the home page, users are mostly unaware of the file structure or URL formatting of a site, either on mobile or traditional viewing. But they are easily confused and you want to make their lives as easy as possible.

Even the most savvy person in the room could have trouble determining if they should use the “m.” version of a site or the desktop version of a site when they are on a tablet, and that is because there are no rules or standards for this yet. Every company is doing it differently, and that won’t change for a while.

The best option for your users is for you to sort it out on their behalf, so that they never have to think about what URL to use and when. Doing everything on one URL eliminates this question altogether, but if you can’t do that or you need very different design layouts on the pages, user-agent detection and redirection from your desktop site to the mobile and tablet versions of each page is the best answer.

User-agent detection and redirection schemes may be the best for your users because they can be based on screen size of the device, the mobile browser or the specific device user-agent. You can have different pages pulled based on any combination of those things. It can get quite complicated, but there is a handy mobile redirection script generator tool that can help you with writing the necessary code if you need it. In my experience, users have the following opinions on this topic:

What Do Marketing Managers Want?

Remember that when you are working with marketing directors or brand managers, they care about more than just the website — they care about offline marketing and email, PPC, banners, partnerships and apps.

They are trying to keep lots of groups happy and coordinated. The question about how to manage and maintain the mobile site structure impacts many other marketing initiatives including apps, SMS, QR codes, print & outdoor marketing, and online advertising.

Marketing managers want mobile content that is reliable and easy to promote in a variety of different ways. They may lean towards a one-URL system, simply because it makes it easier for them to know that they are always promoting the correct URL, and not have to use different URLs for mobile and desktop, or possibly different URLs for tablet and mobile.

On the other hand, they may prefer mobile-specific URLs, so that the landing page experience is more tailored for the handset of the user, so that they can promote OS-specific app downloads or so that they can easily track mobile and desktop traffic to the site separately.

This is what you will be told if you discuss mobile site structure with a group of marketing managers:

What Do Developers Want?

Developers are a hard group to please, and they can have a variety of objections to the numerous SEO and mobile requests we put in front of them. Their basic goal is to keep the site up, functioning and preforming at its peak with minimal fire drills and emergencies in the middle of the night.

Some would probably prefer one URL site architecture, especially if they are strong in HTML5, CSS3, jQuery and other Responsive Design tricks that allow them to show off their skills. Others might prefer to work with redirects on the server, and let the designers go nuts designing loads of different templates for every device imaginable.

Their opinions will be varied, but one thing that is certain is that developers are under even more pressure than everyone else. They are expected to understand the needs of all the different groups and then actually build pages to meet those needs and expectations, whether they are reasonable or not.

Here is what you will usually learn if you discuss this question with a team of developers:

 Conclusion

So just like any good SEO question, the answer on this one is “it depends.” The decision to use a one-URL strategy to reach your mobile audience or to build mobile-specific pages on mobile-specific URLs really does depend, not only on the type of content and experience that you want to create, but also on who is really deeply involved in the decision making and planning process.

Everyone will likely have slightly different opinions and experiences, but it will help to remember where they are coming from, what their goals and KPIs are, and then you will hopefully be able to derive a strategy that will please at least some of the people, some of the time.