I really dont understand the issues some have with the GUI effects.
I have a Titanium PowerBook. It has 768MB RAM and a G4 @ 1.25 GHZ (not a consumer model) and a Radeon Mobility Pro 9000.
Thats pretty crappy specs really. I do NOT have a transparent menu bar. Other than that, everything works smooth as silk. I did NOT expect it to be so smooth, especially spaces. There is no horizontal tearing of dock icons with magnification on. Dashboard comes and goes fine and expose is great.
The only time I have slow downs is when I am doing really intense CPU stuff, like playing Sim City 4 Rush Hour in a window while surfing and chatting.
I just dont understand how people STILL do not realize that this is primarily a Nvidia driver issue. the VASt majority of ATI carded folks have smooth animations. go figure my 2K MBP sucks...