I think there are a couple of parts to social networking: intimacy and performance. I wrote more about that here: http://blog.byjoemoon.com/intimacy-and-performance-on-facebo...

I think the problem is when you privilege performance over intimacy, which privately owned and operated social networks have incentives to do.

Which is one of the many reasons I'm rooting for a decentralized, distributed social networking solution. I've got high hopes for tent.io, for example.