I couldn't agree more. I use Audition/Cool Edit Pro at work (radio production) and have yet to find a suitable replacement for it on the Mac. Soundbooth has very limited usability without being able to bounce tracks into an integrated multitrack.
What's sad is that when I saw all the audio apps available for the Mac I thought Audition level functionality would be easy to find. I couldn't have been more wrong. I have tried Soundtrack and Peak, and each are good in their own way, but neither fill the needs of a typical radio station production load. It is very frustrating to me. Ironically, I sent an e-mail to Adobe just the other day requesting that they port Audition...when I saw the headline about Soundbooth, I got really excited until I realized it was a port of Cool Edit 2000. Still, I downloaded it and will test it on my iMac.
Please Adobe...give us Audition!