I see the debate on other forums about that DX12 will not see any adoption because of numerous reasons.
DX12 was developed by Microsoft with VR in mind. It is exactly why Johanson from DICE was talking with people around the industry about giving the developers more control over hardware if VR is supposed to launch. That is why AMD even first skeptical, started development of it, and after first experiments it was apparent that it will be great thing. From this came Mantle. You may not believe it but it revolved around VR and HSA 2.0, and future specifications of HSA. It had to be open source if it was supposed to be a big hit, and it was: Vulkan and DirectX are gaming VR APIs. LiquidVR and Metal are frameworks for graphical compute, and there will be third API - workstation, CUDA-like, that is revolving around HSA 2.0. And yes, it will also be OpenSource. For the reasons that in another paragraph of this post will be more clear.
I was a bit skeptical about VR. Until I saw demo from Ubisoft. It was simple demo of flying as bird over the city. But it was fantastic idea. And VR in future is everything and everywhere. Cars(!), education, entertainment(films, games, interactive books),
HPC,
Workstation, home usage, smartphones, computers, even UI. EVERYTHING. This is the market that AMD targeted. Im not saying that this is good thing that one company is going for monopolizing it, but... at least the solutions are Open Source, not proprietary. So if someone will come with better hardware for the software solution - it will always win. And yes, currently for VR, and low-level access to hardware and application better hardware is AMD branded.
Mantle is everywhere currently. Apart from workstation and HPC market. But soon it will be there also. At least a derivative of it
.