As I posted yesterday, I have moved over to intrepid.
I have noticed a few major improvements over hardy (for me, on my hardware), but a MAJOR improvement is the way that video is handled in windows that are being moved. It just works. Perfectly.
Here's an example - I have totem playing the big buck bunny, and mplayer showing a home movie of the family in Italy. Rotate the cube... and it's no problem!
( BTW - I did a sanity check and confirm this isn't/wasn't the behaviour on the same machine in Hardy.)