Jason Kotke hit it right.
"One of the new features of FriendFeed (a Twitter-like thingie) is "fake following". That means you can friend someone but you don't see their updates. That way, it appears that you're paying attention to them when you're really not. Just like everyone does all the time in real life to maintain their sanity. Rex calls it "most important feature in the history of social networks" and I'm inclined to agree. It's one of the few new social features I've seen that makes being online buddies with someone manageable and doesn't just make being social a game or competition."