When that story originally came out this week, somebody crunched the numbers of the percentage of target-age internet users that actually exist, taking out Chin

When that story originally came out this week, somebody crunched the numbers of the percentage of target-age internet users that actually exist, taking out China and other places where Facebook is blocked, and users too young to actually consent to be on there. I can't find it now, but Facebook's user numbers were approaching saturation. So there's not really anywhere to go for exponential user growth, unless you admit that most of your users are bots, and that it's a stupid metric. At some point everyone who wants a Facebook account has one.