In Defense of Twitter, from Vincent Andres
Stefan was saying twitter is so brilliant because it's like fast food on the Internet.
Twitter is what we do with it. So indeed there's a lot of fast food, but there are also very interesting accounts, giving information on science, open edition, etc.
Nobody is forced to subscribe to uninteresting accounts, and there is no lack of interesting ones.
More open than twitter, there is identi.ca … and even more open is status.net (on which identi.ca is based)