I'm going through my list of Facebook friends and I'm deleting everyone I don't know anymore. It's one thing to have known someone (as in you went to school with them for 6 years...) but when you fall upon their profile to see that they're in some other country doing something you never thought they'd be doing and either you haven't spoken to them since you've become friends on Facebook or you've never talked to them in person, then you may as well be a complete stranger to me. Therefore, I'm deleting you from my list of friends on my Facebook.
It's actually sort of depressing. I go through all these people and it occurs to me that I barely ever knew them at all... It shows me just how few friends I have. But I guess in the end I'd rather have a handful of true friends than hundreds of strangers called friends.