Well, humans like to have all there stuff in one easy to find place.

Thus, if f-c-book was honest, open and cared about user privacy, it would be the greatest thing. But they're not.

The future will be much different; inside out.

Everyone will have a "wall" server.
And they will post their stuff on their wall server and allow access to it by the friends that they select.

There will be wall viewing softwares that will go out and pull all the pertinent stuff from all your friend's walls, and display it, probably something like f-c-book used to look like.