Brad Fitzpatrick and David Recordon have a doc up called Thoughts on the Social Graph. The aim is to hook join up one's IDs across the various social networks, with an eye to making the data portable. Great stuff. Brad's already started implementing, he mentions FOAF in the post but it's not clear if that's the direction in which he's going, in his slides he's talking graph , but uses "claim" and "is" arcs (which should be directly RDFable). Not sure if he's aware of SIOC etc. They've got a mailing list - I already mentioned LinkingOpenData and microformats/ GRDDL there, but a bit more encouragement couldn't hurt...
See also: blogosphere responses via Techmeme
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