A few years back, I started getting interested in a similar idea. I'm definitely intrigued in seeing how well it goes. Good luck to you. Of course, as ideas go, I allowed myself to think further into the possibilities, and found some interesting avenues. For instance, why allow the facebooks, twitters, etc to own domain over our content? Let people store their own data, and offer API endpoints giving facebook, twitte…
I have also thought about this idea that users of a social network could keep all their data and just let different clients (Facebook, Twitter) access it. I think it would be a great idea! If I want to change my email address? Change it in one place. If I want to let my friends know something? Update it in one place. It's very DRY you know? But then I think, why even let Facebook use my data? If we have these data st…
1.) Go to web page and use application, or 2.) Download app and use application
This is how Facebook / Twitter / etc. do it., and they're clearly doing it right. But there's no law which says that the application needs to keep its data on a third-party server. Why not have it run a Peer-to-peer service?
In fact, I think that Peer-to-peer is especially suitable to social networking, given that social networks are typically highly clustered (eg., people who are my friends are much more likely to be each others' friends as well). This means that if the every client application is able to redistribute copies of friends' status updates as well as its own status updates, then a sync between any given pair of clients is likely to allow them to bring a large subset of their friends' statuses up to date.
Of course if you're rebroadcasting your friends' status updates as a P2P host, then the question of spoofing/authentication becomes paramount. Obviously that would have to be solved by having all status updates transmitted in encrypted formats which can only be decrypted / authenticated with a users' public key.
Oh, and once you've got dual-key authentication embedded in widely-used social trust networks, you could probably solve a lot of other authentication problems while you're at it.
All of this would need to be completely transparent to the user, of course. If it's any more difficult to set up and use than standard Facebook / Twitter, it will fail. But I don't see any fundamental obstacles to making it that easy.
Unfortunately I don't have time to do anything about this!