Facebook's blog post actually says "500 million people all around the world are <i>actively</i> using Facebook" (emphasis mine), which makes this much more impressive.<p>Though I'd like to know what qualifies one as active. I'd also like to know the total number of registered users.
How big do you all think Facebook can reasonably get to? I have to think it's going to be difficult for Facebook to grow anywhere near as fast as they did to this point unless they can get to China.<p>It seems like most US companies (search, portal, etc.) haven't done very well in China - will Facebook be able to buck this trend?
Facebook's user population has been larger than the US population, ~300 million, for about a year. Facebook, considered as a nation, would have the 3rd largest population in the world. To move into 2nd place, Facebook would have to pass India -- 1.2 billion users/citizens.