I agree that running 11.04 in a VM is a bad. Unity requires compositing and
that does not work in a VM. You can test 11.04 with classic GNOME or Unity
2D, but it does not give an accurate picture of where Canonical is headed.
It would work with most other distros and any other version of Ubuntu, but I
have been trying since January to get a good experience of 11.04 in a VM. I
can run it, but not with Unity (only 2D Unity which is available by PPA
only). GNOME 3 just plain does not work with my ATI card even in a full
installation. It flickers so bad that it is unusable.