Some anecdotal Vista RTM performance observations.

Nwn2 in vista.

It shows up in the game explorer. A nice touch.
Running it with the same settings in XP, using a beta ati driver not optimized for nwn2. Same AA and AF settings, same rez. I get about -4 -5 less frames. However, in XP, with AA activated I get a "fading" bug effect in menus that is not apparent in Vista.

Running in vista has hot bar corruption until I did this little fix:

[HKEY_LOCAL_MACHINE SOFTWARE Microsoft Direct3D]
"DisableThreadedDDI" = dword:00000001

1. open regedit
2. navigate to HKEY_LOCAL_MACHINE
3. then software
4. the Direct3D
5. then add the dword value DisableThreadedDDI
6. the value should be set to 1

No corruption now.

To get those 5 extra frames in XP i had to do the following:
Activate triple buffering for D3d games, run a custom driver optimized for nwn2 and I get some flickering on load screens. Vista has no flickering.

Over all, I'd say not bad. It's almost about equal, I think the extra 5 frames in xp are probably coming from the optimized driver from tweaks r us. I'd love to see a non beta driver for Vista. Also, I'm still using the generic nforce 4 drivers that vista loaded for me..so there might be a performance increase when and if I load up the vista nforce 4 drivers.

I'd be interested to see what other people are getting with various games.