The biggest complaint seems to be that Android is software rendered. As of 3.1 (i think, maybe 3.0) this is no longer an issue as a single line in the manifest will cause Android to automatically accelerate your drawing if possible.
It works pretty well... except for software input method (the other name for the touch keyboard).
A simple example: make a webview that scrolls down and ends with a textfield a couple screens below. Activate Hardware acceleration, scroll, touch the textfield, boom, the textfield remains below the keyboard so you don't see what you type.
Deactivate hardware acceleration. Do the same test. Boom, the screen pans up and the textfield is visible.
Once you've done this on a xoom, try it on an iconia or whatever other tablet you have.
I've yet to actually try it though :)