I find that "the network effect is pretty strong" is an understatement. Facebook is not just a social network, it's a pervasive platform. Not to mention that FB

I find that "the network effect is pretty strong" is an understatement. Facebook is not just a social network, it's a pervasive platform. Not to mention that FB and Myspace were fairly different (Myspace accounts were a mess), and right now G+ seems to largely be a FB clone.