A state tracker named d3d1x has been committed to Gallium3D. This implements nothing other than DirectX10 and DirectX11 API support for Linux.
Luca Barbieri made the commit available on Mesa and describes this as an important step in delivering on the promise of multiple graphics APIs on Linux. He also points out that a second objective is to run Windows DX10/DX11 games on Linux, using Wine.
The difference now is that the implementation isn't a mere translation of DirectX 10/10.1/11 to OpenGL on Linux, but genuine native support with a micron-thick wrapper of code. This will allow Linux (or just about any Unix-based system) to run Wine and DirectX-based applications and "should not result in detectable overhead", according to Barbieri.
This does not apply to DX9 and older implementations as from DX10 onwards things changed substantially and warranted, if not facilitated, the new API.
According to Barbieri the system is up and running as of now, and you can download the commit from here. It already contains its own demo code which you can compile and then run. Feedback and input from debuggers/testers is welcome, we believe.
Linux and 3D have had a love/hate relationship for a while now. Despite some attempts at getting (3D) apps ported to Linux, the reality of Linux gaming has progressed more down the path of technical 3D applications and usually involving rather dated OpenGL performance.
This must be the best news Linux gamers have heard in a while.