I use Twitter. I've had the account for a while, but only started using it heavily in the past month or so. I've been pleasantly surprised by the useful links and info that people post there. The secret is to find some decent posters to follow - there's a wide variety of the quantity and quality of information posted. Personally, I don't mind it when a Twitter-er posts personal information (e.g. what they're having for lunch) but I can see where some people may want to stick to posters that only post "professional" information. http://whoshouldifollow.com/ is a good way to find people. (Link courtesy Jim Milles' Twitter - See! Lots of fun finds on Twitter!)
I use Twitter too. So far, it's been for the "what I'm having for lunch" variety, but I'd like to explore professional uses of Twitter. Can we use it to communicate with library users? If so, for what types of info exchanges?
They seem to use them for "emergency messages" (i.e. the wireless is down) or to announce up coming events. However, given the two-way communication that I've been witnessing on Twitter, I think it would be interesting to see if a smaller, more contained library (such as a law library) would be able to use it for answering basic ready-reference type questions.
Twitter -- I'm still experimenting with this kind of network and I thought it would be best to use the larger one (though Twitter is also famously unstable). Thanks, Lyo, for that neat recommendation link - lots of great recommendations, but it thinks London is near Oak Park!
Is anyone using FriendFeed? I have an account there, and I follow it through Google Reader, but it doesn't have the immediacy that Twitter does--I only get updates once or twice a day. I've tried using FriendFeed with Twhirl, but then I get too much information, and most of it is redundant because I get the Twitter feeds in FriendFeed as well.