I was told by Adobe sales that Audition will not operate with Vista, in fact they only have a couple of programs that will so I suggest that if you are planning a system upgrade to wait till later this year when Adobe has programs that are Vista ready ...
Sorry for my absence. Getting busy around here as we're wrapping up work on some stuff.
Audition does run on Vista, although it turns off the Aero interface if you're using that. Once it's closed, Aero is re-enabled.
If you're using Vista and doing ANY performance-sensitive work (such as recording, video editing, etc) I highly recommend changing to the Basic Vista theme and NOT using Aero. We're seeing really incredibly poor performance problems with it on - some really random USB bus issues, screen drawing issues, etc - even using Windows own libraries on some pretty beefy systems.
I haven't spent too much time with 2.0 under Vista - but enough to say that it runs fine. The biggest problem is a new lack of drivers - a lot of the ASIO drivers that worked great in XP do not work or only partially work under Vista. Vista also changed the way applications see device channels, so you may notice some weirdness when setting up recording inputs.