As we look to the future, maintaining a proprietary IR format (even one based on an open-source project) is counter to our commitments to open technologies, so Shader Model 7.0 will adopt SPIR-V as its interchange format. Over the next few years, we will be working to define a SPIR-V environment for Direct3D, and a set of SPIR-V extensions to support all of Direct3D’s current and future shader programming features through SPIR-V. This will allow developers to take better advantage of existing tools and unify the ecosystem around investing in one IR.
↫ Chris Bieneman and Cassie Hoef at the DirectX Developer Blog
SPIR-V is developed by the Khronos Group and is an “intermediate language for parallel computing and graphics by Khronos Group”. I don’t know what any of this means, but any adoption of Khronos technologies is a good thing, especially by a heavyweight like Microsoft.