I signed up for Twitter recently you can follow me if you like I’m mark_wingfield on Twitter. Having played around with it a bit and talked to people I know who use it a lot it seems to me like the most closed of the popular social networking systems. Myspace seems to be the most open (whatever you think about its content) in that anyone can easily connect to anyone else and does. It has its own Twitter like feed that a lot of people there seem to use, though it sits right inside this huge completely open social networking tool. Facebook seems sort of in the middle. Its semi-closed in the sense that only your friends can see information about you, but you can also freely connect to more friends via friends, the point being that you can do this at will. Twitter seems to me the most closed of the three systems. There is no open networking, you can’t find out much about anyone you come across, and although you can choose to follow them, there’s no particular inclination for them to follow you ie there’s no actual connection. Most people I know just communicate with a small group of real life friends and follow a few celebrities or interesting people who they don’t know. So its a very closed system. This isn’t in any way a criticism of Twitter. So far I can’t see any use for it in what I do. However I am still experimenting and am open to ways I may not have seen yet.