One of the liveliest topics at sxsw was social network portability. In a sesson on the topic, the panelists
panelists, including David Recordon, Chris Messina, and Joseph Smarr were unanimous that the value proposition of social network portability is to enable data to flow freely between services. The metaphor they used was “vaseline for the web.”
There are any number of situations where users may not want their social graphs and identities combined without friction (health support group, religious groups and other subcultures, political groups, etc). Brad Templeton, EFF board chair, got up and talked about privacy, but his message seemed to be falling on deaf ears.
After the session, Chris Messina wrote a post that may be helpful. He suggested stripping down relationships to rel=me and rel=contact. With that, finer-grained denominations of relationships, actions (notifications, publication, invitation, sharing), and permissions can be handled at the application level. This would be a very good thing.