Steam System Statistics

Every month, Steam collects hardware data that their customers use. All statistics can be viewed on their website. I think this material will be especially interesting not only for game developers, but also for everyone else.

You can immediately see the superiority of Nvidia / Intel over Ati / Amd. Half of the users have a channel width greater than 2Mbps (but say, there is no life beyond the Moscow Ring Road =). Amazingly, almost 70% of users have DirectX 10 GPUs, and only 29% of real DX10 systems. But given the growing popularity of Windows 7 (already 10% in incentive), this number can change very quickly.

In general, see for yourself. Everything is pretty detailed there, and with convenient sorting.
ps The picture is clickable.