If you mean G+, of course it's no different. If you mean email, typically only governments and courts can get access to that without hacking. I don't feel it's as insidious as daily public postings.
True, but most facebook friends rarely, if ever, merit an actual email. And when they do, unless they are also in gmail, it won't trigger as large a cascade of edges gaining weight in a massive social graph.
Oh that's right. It isn't. Which makes this idea that Facebook is going to die as realistic as Google is going to die.