For those interested, Microsoft will be offering full games for download through their Games for Windows LIVE system. 4 games have been announced which will be available at 15th of Dec. Tinker and Texas Hold Em' will be available to download for free while Osmos and World of Goo for a one time fee, no costs have been announced yet as of this moment. Windows XP and Windows 7 have been confirmed to support Games on Demand, no news so far for Vista. Sorry Vista users.
You know what this means for PC gamers, more achievements! Is Microsoft trying to compete with Steam? How will steam react to this move? Only the future will tell. I'm just happy there are more games available. :D