Isn't this kind of what xmpp or pubsubhubbub are about, decoupling the data created by a user from a service? I think it would be interesting to see this combi

Isn't this kind of what xmpp or pubsubhubbub are about, decoupling the data created by a user from a service? I think it would be interesting to see this combined with the personel web server concept seen in Opera Unite, to serve an xmpp feed from an individual user (and device) that is ingested by multiple services. This would give users control over their data (they have a local copy) while allowing it to exist in the cloud as well. The user would also be able to publish "deletes" to tell services indexing her stream to remove a previously published message. Having control of ones data is extremely important however. A push for existing web services to have an open intermediary data is essential, users should be able to backup or migrate their data with ease.