Driver are still to be ironed out ... especially video drivers.
Nvidia, as every one knows, is far far behind.
Ati's have caused me numerous problems from BSOD to hangs. Some of this may be the new audio subsytems and interactions with it.
3 BSOD ... all identified as being ATI drivers
3 Game hanges (CTL-ALT-DEL used to cancel task). All id'ed as ATI
2 Reboots ... probably because of my overclocking
W95 and XP had the same growing pains. Being a gamer, I remember waiting for both patches and driver fixes to actually play some games. There were no system tools, etc etc
The BIG thing for Vista will DX10.
Company of Heroes promises a DX10 patch in Feb
Supreme Cammander pomises a DX10 patch in March
C&C3 is suppose to ship with a DX10 patch.
Then the official DX10 games ie Crysis
May be time to buy 2 x 8800GTX's for my computer