A recent forum post by Microsoft employee Daniel Moth indicates that DirectX 11.1 is exclusive to Windows 8, much the way DirectX 10 was not released for versions of Windows before Vista, saying it is integrated into the new version of the operating system. Here's word on where this stands right now: "DirectX 11.1 is part of Windows 8, just like DirectX 11 was part of Windows 7. DirectX 11 was made available for Vista .... but at this point there is no plan for DirectX 11.1 to be made available on Windows 7." Neowin was told "we have nothing further to share" after contacting Microsoft for further comment on this. The biggest difference between DirectX 11.1 and DirectX 11 seems to be native stereoscopic 3D support, so this should not impact serious gamers anyway. Thanks VG247.