Need for Interconnected Social Networks

I came across a post written last year by Dave Winer. In it he talks about the importance of interconnected social networks.

“Closed systems are fine in the early stages of a new technology. They're the training wheels for a new layer of users and uses. But, as we always see, the training wheels eventually come off, explosively, creating new systems that throw out the assumptions of the old.”
Dave's wishes, to some extent are getting fulfilled by Google Friend Connect and Facebook Connect: Two services that attempt to make social graphs portable.

“Eventually, soon I think, we'll see an explosive unbundling of the services that make up social networks. What was centralized in the form of Facebook, Linked-in, even YouTube, is going to blow up and reconstitute itself. How exactly it will happen is something the historians can argue about 25 years from now. It hasn't happened yet, but it will, unless the rules of technology evolution have been repealed (and they haven't, trust me).”