Though it was sort of announced by Treyarch in a post on the Call of Duty forums, Valve has now officially confirmed that Call of Duty: Black Ops will use Valve's Steamworks for auto-updating and achievements. It'll also use the Steam Cloud for storage of profile and configuration settings. The game is available for pre-order now on Steam.

If you're wondering whether your computer will even allow you to play it, Treyarch also announced the minimum specs. You've got 12GB free, right?