In November 2008 Facebook drew 200 million unique worldwide visitors; more than 1 in 5 people who accessed the Internet that month visited the site

The team at Pingdom, a firm that focuses primarily on uptime and performance, has posted a new blog entry estimating that Facebook will overtake MySpace as the top social network in the U.S. within a month or two. That's largely because, according to the same numbers, Facebook has doubled in size in the past year.