I am 1000% with you on the need for a decentralized version of the social graph, or social networking, or social media, or whatever the in-term is these days. People don't realize just what they're giving up with the mega sites.
Also, Palantir.net and GoingOn have been collaborating on some cool stuff with PubSbHubbub recently that we are planning to release very soon, just as soon as the project it was written for launches. Details will show up on the Planet, but for now I can say Views + Feeds + PubSubHubbub + a little fairy dust = Sweet. :-)