I'll switch when there's a dominating replacement. All I want, for the rest of my life, is:
- a way to see updates from friends and acquaintances and people I've fallen out of contact with, and post mine for them.
- a way to search for and 'add' people I meet.
- a way to chat with those people (including in groups)
- all of those things, without social baggage that constrains it to 'only teenagers' or 'only colleagues and classmates' etc.
- and in a network that contains most people I meet, or doesn't have social baggage that prevents most people from being willing to join it.
To me it's an enriched version of what I get by having lots of contacts in my phone or email address book: exactly a list of people, plus the additional fact that I feel physically near them in some sense (and I think this is a concrete emotional thing. My family and friends don't feel too far away when I get to see snippets of their life streamed into mine).
Everything else - groups, events, pokes, company pages, apps, games, friend suggestions, wall posts, public about-me sections, places, reviews, ads, etc... I don't care about any of it. Maybe something that trims off all this fat would be innocuous enough to actually find adoption. I could see it living in some peer-to-peer structure too, but it has to still be absolutely trivial for anyone to join.