According to Twitter.com, “Twitter is a service for friends, family, and co–workers to communicate and stay connected through the exchange of quick, frequent answers to one simple question: What are you doing?” However, it has the potential to be much more than just “I’m drinking coffee” messages. To be honest, most of us don’t want to know what you’re doing every minute of the day. The Twitter competitor Pownce describes their site much better: “Send messages, files, links, and events to your friends. Create a network of friends and share stuff.” Pownce is marketed as being a communications tool, sort of like public/private IM.
I think of the two services as a sort of IM service that you needn’t be logged-in to receive messages. They’re, to me, public IM. Pownce is leading in that aspect (marketing themselves as an IM-like service rather than a system to tell everyone what you’re doing), but unfortunately, everyone uses Twitter, and therefore sees the notice on the main page that says “What are you doing?” I’d like to see less of that usage.
I recently created a Twitter account, and it’s interesting, though it threatens to be a major time waster (and why must their API have a 70 request per hour limit?). I haven’t actively used IM in years, and I don’t have a cellphone, but Twitter so far has pulled me in. I just use it as an IM service/link-sharing system/Tumbleblog (and I have WSC’s feed auto-posted 
).
What is Twitter? It’s IM 2.0.
