After some hesitation, Microsoft has finally confirmed officially that DirectX 11.1 will remain a Windows 8 exclusive for the foreseeable future.
Microsoft employee Daniel Moth confirmed that "at this point there is no plan" to release the latest DirectX update on Windows versions other than Windows 8; not even Windows 7.
DirectX 11.1 is a minor update over DirectX 11. The most important feature it adds to DirectX is stereoscopic 3D rendering. However, the decision to make it a Windows 8 exclusive implies that upcoming DirectX updates are likely to follow suit.
A lot of game developers and publishers have expressed their resistance to Windows 8. With this move, it seems that Microsoft will stop at nothing to force people to move on to Windows 8.