Facebook is literally holding back the Internet, the biggest tool for human evolution, dialogue and understanding ever invented. Their platform is the lowest common denominator of everything the web has to offer.
Through gaming, IRC, alternative social networks and forums I've made friends from every major region of the world and got to know them pretty well- how they live, what they think, etc. I've never made a single Facebook friend I didn't know in real life or had any single interesting discussion on the site since joining it years ago.
Maybe you, a blessed Internet soul have done so but it's obvious that the average person only uses FB to keep in touch with family and friends. A recent Internet research showed more people "use Facebook" than there are people who believe they "use the Internet". Your average moron can't even tell that Facebook is part of the Internet, let alone know the Internet has better alternatives to everything Facebook does...