Has any one been paying attention to what they've been doing? One interesting concept that's raised in their implementation and something that Marc Canter often talks about, is the idea of subscribing to parts of a person. In other words, subscribing to a person's blog is one thing you could do, but what if I wanted to subscribe only to their recommendations, or the pictures they post, or the events they create (or will be attending)? Wouldn't this be interesting? In other words, decouple what it is that interests us about people and only follow that. Anyone else think that the concept has legs?