Microsoft has confirmed that DirectX 11.1 will be made available for Windows 8 only and that Windows 7 and previous versions will not be getting it.
Wrote Microsoft’s Daniel Moth on Microsoft Answers:
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.
DirectX is a suite of technologies used by many of the multimedia programs in Windows. It is developed by Microsoft to provide hardware acceleration for heavy multimedia applications such as 3D games and HD videos.
DirectX 11.1 adds native stereoscopic 3D support. That is, PC games written with DirectX 11.1 will have support for viewing content with stereoscopic 3D glasses.
This could indeed be bad news for many Windows 7 users who were not planning to upgrade to Windows 8, and were instead waiting for the DirectX 11.1 update.