I came home from FOOcamp with my mind buzzing with something similar. It was in the zeitgeist, I guess.
Between being annoyed at some of 6As recent actions, and annoyed that if I left LJ, I would lose a lot of valuable social network information. And then the sessions on distributed social networks, openid, oauth. And playing with the CrowdVine social network software that had been set up for FOO.
And then I added in my own current hot interest, massive utility grid computing, and the attendant fall in price and ease of access for users to buy really cheap really transient processing.
And I had a vision.
- The "next gen FOAF format/protocol", distributed federated social graph data, like you have just excellently described.
- And social attribute claim data (X's name is, X's birthday is, X's interests are, etc)
- And the concept of the small start-your-own social network app, like CrowdVine. Only cranked even farther up/down. Instead of for a small cluster of people, its just for one person.
- And run it on the coming tide of uber-cheap, transient processing, with persistent storage.
Everyone could run their very own "social networking site", that would be all about just them. Sort of a "blog, squared". And that it could interop with the other "sites of one", and also interop with all/most/some/any of the current and future Big Systems.
A person could have something that will work and look and feel almost just like their current LJ / MySpace / Facebook / Vox / Friendster / Tribe / etc accounts. But it would be theirs, no longer subject to threat of deletion/distruction at corporate whim.
It could be easily hosted, either with the current model of renting a cheap hosting provider, like Linode or something. Or via the next generation of transient computing, like the successor or evolution of EC2. So if it's not doing much, it doesnt do much, and if it's suddenly called on to do a lot, it can burst up as needed.
Probably a good design for a "system of one" would have the basic core to handle the netgen-distributed-FOAF stuff, and the core of publish/subscribe (I'm thinking something like gdata, Atom over HTTP with TLS).
And then common modules for skins, blogging, images, presence, instant messaging, additional access (email from phones, SMS), "hot what" (Twitter / Dodgeball / etc).
And then a whole pile of more modules, which can barely be conceived of yet. Shopping agents. Wallets and value stores (maybe with a live network connection to a cryptoprocessor in the user's physical possession). Financial tracking/alerting/autotrade. Clipping service. Automatic secretary / personal assistant. etc etc etc.
There doesn't and wont be only one implementation, either. Many many can be written and deployed. As long as they mostly possess as sufficiently overlapping set of mutually understood protocols...
I think that this is more or less the way things are going to go.
The current silos are going to be as snowballs in boiling water. Their users are going to jump ship as fast as low-pain migration tools can be written.
There is going to be no more huge money in running a "basic" social network site at all. About the only good feature such will be able to offer will be hand holding, attempts at uptime guarantees, and resistance to DDOS / slashdot effect / instalanch.
The social graph will stop being something that people make money with, and become something that people make money because of. There will surely be lots of money to be made, via applications that haven't been realized yet and are not possible yet.