Ok, I have been playing around intensively with Audition CS5.5 for a few weeks now. Aside from the thing that SES to SESX import did not work natively (thanks Todd, for giving me the link, although I do think that it should have been included in the software in the first place), there are some other things that bug me.
Here's my top 4 (in order of personal importance):
1. GROUP CLIPS
This feature is missing. If you're working on a mix, you need to be able to move parts quickly, not risking screwing up parts that are OK. Manually selecting all clips and then moving them is timewise not very efficient. IMHO, we really shouldn't have to wait until CS6 for this feature to return...
I keep hitting the vertical zoom sign whenever I want to zoom in horizontally. I use horizontal zooming much more than vertical. Of course you can use the + or - signs on the keyboard, but I find myself hitting the on-screen button time and again. In Au 3 they were in the "correct" position. And there's no way of adjusting the workspace so that I can place the buttons where I like them to be. I am so used to this on-screen layout, that I think it will take a long time to adjust to this.
3. CLIP TIME STRETCH
You can't drag clips to stretch them to a desired length. You do have an improved dialog for Strecth and Pitch (which I like), but you can't do it visually on the timeline.
4. PRE-LISTEN TRACKS
I Au 3 you could quickly sort through multiple effect tracks by pre-listening them using Auto-play in the import dialog to find that right type of swoosh you need from your sound collection. Now you can't, or you have to rely on Adobe Bridge.
I know that the Adobe Bug Report / Feature Request form is the best way to submit these (and I frequently use that), but I'm also curious if other sound editors deal with the same problems.