[femto]

Communicating in a way that is mutually agreeable is a more powerful enabler of friendship than the existence of an entry in Facebook's database.

I put it to you that Facebook is about group communication, whereas friendship is about one-on-one communication. As such Facebook has nothing to do with friendship, and it is a delusion to think otherwise. Those Facebook "friends" are actually acquaintances, and your friends are those smaller number of people whom you talk to outside Facebook.