No, you have a "social network" because of your social contacts, that doesn't need the Internet at all. Also, the internet consists of more than the Web - e-mail and IM are also fine tools for maintaining your social network over the Internet, for example.

Now, there may be functionality that those services provide that others currently do not, and I never disputed that. But the original argument was that somehow that little fenced garden had a large userbase.

Other than that, I am not sure I am interested in the surveillance, lock-in (potential), and manipulation possibility that FB/twitter/G+/github/whathaveyou "provide".