Apparently the latest cool social network to belong to is This. It’s a small, invite-only network, where the catch is that each user can only share one link per day, emphasizing quality over quantity (like this class!). Of course, the New York Times is On It, so it’s possible This. is passé already, we’ll see.
The Atlantic also has an interesting explanation and analysis of subtweets and what they call “super tweets.” It’s worth checking out to see how it’s done and what it might mean.