I use just one program for all my different chat engines... Called Fire... It is a free download, and I found it at version tracker. It supports all the different services like AIM, MSN, ICQ, Yahoo... I found that the current version doesn't crash on me, even though I might get dropped by some of the services. You can also import your buddy list into it. I don't have an MSN account, since you have to sign up for a hotmail email account and that passport thing. The program works very well with OSX, probably because it was created there, not a OS 9 application that has been ported over.
Since I am in OS X 99% of the time, I try to use native applications as much as humanly possible.
For that reason, I picked up the upgrades for both Illustrator (10) and Bryce (5) yesterday, since they are OS X native now. I look forward to playing with both
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