The main problem relating to speed in Vista is it's background processes (services, etc). You can actually get roughly equivalent performance to XP if you disable unnecessary ones, but that's something the benchmarks never show. They should (have) release(d) Vista : Gaming Edition, one with all the fat removed, I think that's the one distinction between editions which would have actually proved useful.

Videos would be cool.. but not really indicative of differences between settings, especially subtle ones, unless it was downloadable HD quality video.

It's not DX10 in XP though : there are simply settings which aren't enabled in XP, higer resolution shadows, higher resolution water hightmaps(?), etc, which is a dirty trick... but it doesn't mean that it's using a unified shader engine or anything else which DX10 is capable of.

Very High is not enabled in Vista, unless you have one of the 8x00 series cards. The article doesn't make that very clear.

way too much ambient lighting. that's what makes it look bad compared to newer games.

"Strange. According to those charts, Vista doesn't show any FPS gains between 2GB and 4GB of system RAM. It's odd how there seems to be a cap in performance. The article doesn't mention why this happened, but I'd like to know why there's no performance gain above 2GB of system RAM. Any ideas?" Once all available RAM is used up, the computer has to resort to disk swapping, which slows FPS significantly. What's going on here is simply that the PC has more RAM than the game needs, which means that the amount of memory is no longer a bottleneck for FPS (it's more likely the memory speed, graphics card or processor).

it'd be interesting to know how well the games run compared to XP, too. They claim Direct X games run something like up to 15-25% faster with Vista.