Can you see it catching on? Up until now I've considered instant messaging a casual way of keeping in touch with people, but I can see why the format would be good for businesses. Chats with more than two people would be like conference calls, but with a few more seconds to compose your thoughts. I'm much more thoughtful on AIM, usually, because if I phrase something too bluntly I can revise it before hitting send. You get the chance to see your thought as it will be communicated, and edit it before anyone else sees it. With conference calls, whatever you say it just out there -- no taking it back.
Conversely, it could be easy to abuse if you take it too lightly. Email has gotten people in trouble because it feels like such a casual way to communicate, and people have sent inappropriate things to the wrong people. Also, the language for different ways of communicating varies greatly, and business conducted on AIM would surely use different words than casual conversations on AIM. And no spell check! There is all sorts of potential for miscommunication using instant messengers. Mark Foley's AIM conversations got him in trouble last month, and I'm sure there will be many more instances of misuse as AIM becomes more common for business purposes.
News and entertainment sources are starting to catch on: New York Magazine printed the AIM conversation between two writers as they watched the TV show Heroes; it's a sort of first-impression review.