We expect DirectX 12 drivers to be more complete, more performant, and more likely to be available out of the box without a separate install. We expect Windows browsers will want to build on top of DirectX, not Vulkan.
No, Nvidia and AMD including Vulcan drivers. Intel isn't and said they don't plan to. Intel has a HUGE market share thanks to integrated graphics. There are other companies too.
"In his blog published on February 16, 2016, Imad Sousou shared that Intel was selected as one of the leading graphics platform suppliers with Vulkan* 1.0 drivers certified by the Khronos Group Consortium."
"We are demoing Intel’s implementation of the API available on the latest hardware from Intel on 3 major operating systems: Windows, Linux and Android." Intel Engineer: "This really shows the industry is moving towards Vulkan."
Intel sure seems to have been making sure all of their chips are now Vulkan capable. All I can find for "they don't plan to" are what seems like rumors on one forum that are spawned by the current drivers being "unsupported" (but given that they are in beta, that makes sense to me: the storyline here is that they were provided for Vulkan developers to start testing their products and likely testing this driver). It really seems like Intel is at worst being "a little slow" to push Vulkan, but they are definitely not unsupportive.
It's the current reality with OpenGL on Windows, which is why Windows browsers do not implement WebGL with OpenGL, but rather by translating to Direct3D.
Maybe it'll be different for Vulkan, but that would be a surprise.
Chrome and Firefox felt there were sufficient problems with OpenGL driver availabity that they implemented WebGL using DirectX (via the ANGLE project), despite the more obvious mapping to OpenGL.
Is there any reason to believe that, unlike OpenGL, Vulkan drivers will be sufficiently widespread for browser vendors to use it on Windows?
Intel has no stated intention of releasing production-quality Vulkan drivers for Windows. Forum statement from August:
The current Plan Of Record is that Intel® is not supporting Vulkan on Windows drivers. The drivers that were made available on Developer.com are intended for Vulkan developers.
So, it is expected that some Vulkan drivers may not work for end users.
Sony has historically supported a variant of OpenGL on the PS3 (in addition to their low level API) - I would be surprised if they don't have one for the PS4.
I worked on PS3. PSGL is the half-truth rumor that refuses to die. It was an experimental GLES1.0 with Nvidia's Cg shaders as an extension. I don't think any games actually used it.