New numbers reveal that Facebook's growth has leveled off, and even declined in some areas.  ComScore statistics show that the number of unique U.S. visitors actually decreased by 800,000 (two percent) in January following several months of slow growth.  Meanwhile, Nielsen shows that the number of Facebook users in the United Kingdom dropped for the first time since being tracked in 1996.

This news has fueled some speculation that Facebook has peaked, and super blogger Robert Scoble argues that Facebook's limitations are causing some users to lose interest. However, analysts point out that Facebook has grown dramatically over the last year and could see significant growth in the future. And, as Erick Schonfeld notes, the number of unique visitors to the site world continues to see modest growth.