By Farhad ManjooPosted Thursday, Dec. 3, 2009, at 5:20 PM ET

Nearly a year ago—in the course of cajoling people into joining the ubiquitous social network—I marveled at Facebook’s astonishing growth rate: The site had just signed up its 150 millionth member, and about 370,000 people were joining every day. “At this rate,” I wrote, “Facebook will grow to nearly 300 million people by this time next year.” I confess, though, that I didn’t think it was possible for the site to keep growing at that rate. Every hot Web site begins to fade at some point, and back then, the tech world was enamored of an upstart that was gaining lots of attention from celebrities and the media—Twitter. Even Facebook seemed scared of the micro-blogging site. In June, it redesigned its user pages to display updates as quickly as Twitter does, a move that prompted a barrage of threats to quit.

Those threats were empty. And so, it seems, was any threat posed by Twitter. Facebook’s growth rate has actually accelerated during the past year. In September, it announced that it had reached 300 million members, and this week, it passed 350 million. About 600,000 people around the world now sign up every day. Twitter hasn’t released any recent usage numbers, but traffic to its site is flattening. Indeed, it’s likely that Twitter has fewer members than the number of people who play the Facebook game FarmVille (69 million!).

Read on: http://www.slate.com/id/2237376/