I guess I will start the 11.10 post.
The first thing that surprised me is that it has been out for about a week now. I usually don't expect it until the last week of the month. I installed it within VirtualBox on my desktop and work laptop. Some initial impressions:
* Unity seems to be a little better behaved than earlier. In addition, Unity runs on the laptop (Unity on 11.04 didn't run on the laptop). I think I will stick with Unity for a while to see how it goes.
* CDs now automount - they didn't in Unity on 11.04 within VirtualBox. I don't know if that was due to VirtualBox or Ubuntu/Unity.
* I still hate the global menus (the way Apple does them). It might make sense on a small screen where you are practically forced to run apps full screen, but with a large screen the extra mouse movement to get to the menus is a pain in at @$$. It is even worse if you are running a dual or three screen setup and the menu isn't even on the same screen as the app. But there is a way to turn that feature off (see link below, and on Firefox you have to disable an extension) and get the menus back on the apps window.
* What, no screensaver other than a blank screen? And no way to change that without installing a screensaver?
* If you share folder within VirtualBox (for example, I share my d: drive with Ubuntu), you must add you Ubuntu account to the vboxsf group in order to access the shared folder: sudo usermod -a -G vboxsf xxxx, where xxx is your user name
Here is a link that details some tweaks you might consider making:
I'll report more if I notice anything in particular.