Facebook just spent six months rolling back user privacy, appropriating data, and dealing with the resulting outrage. And yet the social network is growing as fast as ever, as neatly summarized in the attached chart from Inside Facebook's Eric Eldon.

With great fanfare, Facebook CEO Mark Zuckerberg announced the social network's 500 millionth user today. More interesting than the total user count, though, is the rate at which Facebook is acquiring new members. Though Zuckerberg has said Facebook's growth rate has slowed to "super-linear" instead of exponential, it's still adding 100 million users every five months, just as it did Sept. 2009 - Feb. 2010 and April 2009 - Sept 2009.

Facebook's controversial changes to its privacy policy resulted in widespread outcry from confused users and some very public account deletions; a chastened Facebook only partially rolled back its changes. We're starting to wonder if even that half-measure was necessary; judging from the speed with which Facebook graduated to 500 million users from 400 million, users would seem to need the company more than vice versa.

[Chart: Inside Facebook]