10.04 by the time I installed it was rock-solid. On the other hand 10.10 is not working properly - web camera is displaying up-side-down and my laptop many times freezes on shutdown. And it's like a cycle, one in every 3-4 releases doesn't cause issues for me.
Unfortunately I don't have the time to deal with these problems, find the cause, give feedback on mailing lists, etc...
If you could invest in a more stable / well-tested Ubuntu release (although I do know the next one is not a LTS) that would be great.
You guys also did a good job regarding usability lately, thumbs up.
The other problem I've had is Compiz (ATI mobility radeon HD 4250). When I enabled the proprietary drivers either it worked nice with No visual effect, or if I chose Some visual effects then chrome of the windows didn't show up until I disabled the effects.
I have then installed 10.04a3 just to try if things were better but now there was nothing visual at all. No bar, no unity, basically all what required Compiz didn't work. When I boot I see only the background and the cursor. If I knew some shortcuts I guess i could still open the windows (but chromeless), but its very annoying.
What I wish for Ubuntu 11 is to polish things up with the hardware. Try to increase hardware support as much as you can, so that users don't have to deal with it.
I may be an isolated case with little luck, but its just frustrating. I think increasing hardware compatibility should be a higher priority than UI polish.