Everyone knows Facebook is a popular site, but new numbers from Experian Hitwise show just how popular it was in the U.S. during the month of January.
U.S. users visited Google+ 49 million times in December, Experian's statistics show. Facebook remains dominant, though, with many more visitors.
The social-networking giant beats out Google for the top spot in the traffic company's annual list of most-visited Web sites.
Visits to the social-networking site more than doubled from February 2008 to February 2009, with growth coming in all age groups except for the 18-to-24 set.
Searches for the still-growing-fast social network dominated last year's leader, MySpace, for the first time, according to the traffic firm.
The traffic firm noticed a clear uptick in U.S. Facebook growth after the site launched Facebook Connect in full, and that's when it passed MySpace in traffic.
Company has its own way of measuring Web site traffic and focuses on competitive intelligence, not ad buying.
The rise of the microblogging service seems to have been hastened by people's use of the site to post musings on an airplane crash.
Traffic firm's analysis of the U.S. social-networking market shows MySpace still gets over 65 percent of the market share but it's gradually losing ground to Facebook.
With a market share topping 70 percent, the denizens of the Googleplex are joining an elite club of tech giants.