You really shouldnt take much from people who admit they only have 10 minutes of experiance with Vista. I have had it since the day it was released, and I like it, and have had nearly zero problems.
Consider that most people get rid of it in 10 minutes because they cant handle the changes made from XP, not because it crashes. The second most people decide to hate it before for the 10 minutes they tried it - back when it reas released, the drivers for it sucked so yes, you got less FPS because nVidia only had BETA drivers - as did almost every company for almost every part.
Right now, I have the latest drivers for all of my stuff and I have both XP and Vista installed. I havnt used XP for months - but when I do, I get between 0-1 FPS more than in vista. However this is because of my hardware. Wats the big difference between 167 and 168 (example only). I have virtical sync on so either way I only get 80.
With a new computer you shouldnt have any trouble - just make sure to get 2GB of RAM and NEVER less (for gamming). With an older computer, if you have trouble running vista due to it's demanding personality when it comes to resources then Obviously you are not going to be able to run games well on it.
hope that helps.