I found the Microsoft MSN for Mac to be far too buggy, to the point of being completely unusable. aMsn was too clunky and also buggy, not to mention it just didn't do anything for me whatsoever. I found it more of a pain than anything else. I eventually caved in to Adium and would never use anything else.
Some people will tell you that it's complicated and requires much configuration, but I beg to differ. I've found it really easy and virtually bugless, the only thing that bothers me is the lack of webcam support.
"See? Gay marriage, a single-payer health-care system, and moves toward decriminalizing pot won't cause the country to implode. They're doing all of that and more up in Canada, for Christ's sake, and the sky hasn't fallen."
You can't send custom emoticons in Adium. I KNOW, its not a big deal but still. If I want to convey my excitement with the animated picture of a ninja turtle dancing around I should be able to.
Lack of A/V sucks too.
Other than that, clean as a whistle
Well it's not windows only but it doesn't appear to have anything to do with msn. I think the original poster was stating in reference to A/V use, that this program is superior to what would normally be used in msn anyways.