This don't change my comment still many of them are fakes. I know people who have 5-6 accounts active at one time playing different games with 500+ friends on it. Many of those "friends" also are fakes, some even with the same profile picture of "real person" with fake data but I have nothing against FB, every medium is abused.

It's just interesting that not a single research was done on this topic that I know about. :)