Valve's November Steam user metrics are up, and it's (still) a landslide for gamers running Windows XP. 68% of Steam users connect to the online community and games service running the 32-bit version of XP. Compare with just 21% running Vista and a DX10-capable video card. Slightly more than that (25%) are running DX10 GPUs on XP, while a sobering 54% still play with DX9-or-below GPUs.
NVIDIA towers over ATI (27%) with the lion's share (64%) of GPU usage. Intel's nibbling crumbs with just 2%. Also: 87% of Steam users run with 4x anti-aliasing enabled, which surprised me, since I have a GTX 280 and often still leave AA zeroed to eek out those extra frames in trade for those highest-of-high level GPU-strangling details.
About 50% of Steam users have dual-core CPUs, a group that's grown steadily since June 2008, while quad-core users appear to have only inched up a percentage point or two in the same period (10%). The remaining 40%? Yep, still running single cores. In all, Intel dominates with 64% of Steam's CPU manufacturer demographic, compared with 37% for AMD.
Bear in mind NVIDIA has an install base in the hundreds of millions, so seemingly small percentages may be misleading here, but only 1.55% connect to Steam with two GPUs in SLI configuration, and just .01% have quad-SLI systems. Makes you wonder why NVIDIA even bothers to support the latter, frankly.
Favorite display resolution? Neatly tied between 1024 x 768 (25%) and 1280 x 1024 (25%).