With a distributed system, the masses could delegate everything to whatever large provider they like the best (FB, Google, etc), but by being distributed, they'd all get to share info instead of being in a walled garden with only other FB, G+, etc users.

So the nutty privacy freaks could happily host their own server, the drooling masses could sign up with whoever's popular that week, and everybody would still be part of one big happy family of people posting drunken party pics... :]

FB will fight such developments tooth and nail, of course...