Decentralized Social Networks Sound Great. Too Bad They’ll Never Work
wired.com
wired.com
Experiments in decentralized social are more of a test run of components for "subversive" networks that will eventually engage the global youth politically on tor rather than compete with fb for grandparents sharing photos and recipes or Myspace as a MP3 storage space for forty somethings with bands.
One hypothesis for why Google+ and others did not "catch on" is because Facebook has orders of magnitude more users, and therefore has reached a "critical mass", meaning no significant amount of users will ever use an alternative.
My hypothesis is that there simply hasn't been a significantly superior alternative yet.
New alternatives can also use Facebook as an advantage by creating a compatible API. Facebook, of course, will "fight back" by making itself incompatible, but the only way it can do that is by making its own platform less usable.
My hypothesis is that you aren't going to make the next Facebook by trying to replace Facebook or make some idea of "the next Facebook". You are going to make the next Facebook by doing something new that isn't very Facebook-like at all.