A new study release by Compete shows an explosive growth spurt of Google+1 and Google+ that started in October. The study represents an whopping 2 million non-mobile users across the United States which equals 1% of overall US users. Compete looked at the stats behind the plus.google.com plusone.google.com subdomains to determine unique visitors, page views and attention for the new social networking features.
As of December Google+ has seen half of the unique visitors of Twitter (20,000,000 Google+ unique visits vs 40,411,065 Twitter unique visitors in December). Since July, unique visitors have jumped by nearly 4x:
The plusone.google.com subdomain saw tremendous growth as well. During the month of October (labeled 40817 below) the usage took-off with approximately 60,000,000 visits in the month of December alone: