This doesn't really make much sense to me...very rich people have their own real-world private social networks already, and unless they're ridiculously wealthy,

This doesn't really make much sense to me...very rich people have their own real-world private social networks already, and unless they're ridiculously wealthy, they probably have lots of not-as-wealthy friends, family members, and acquaintances that they want to keep in touch with too, so now they have to maintain two networks. Seems like they'd just use FB with extra privacy settings or not use anything at all. Also, I like how both of the exclusive networks for the rich mentioned in sibling comments apparently couldn't afford a .com domain name :)