Apple might, but they're already doing Metal on iOS/OSX now, and they've always been slow on the OpenGL front, so I wouldn't hold my breath.
They only said that it's coming this year. I'm also curious about who will support it. PS4, Apple etc. or will they insist on their proprietary solutions?
Sony already have the best API of the current offerings... They could make a Vulkan wrapper around it, to make porting easier for PC developers... But in that situation, Vulkan would be a wasteful high level API that's blocking you from low-level efficiencies
I doubt many developers would prefer that.
Yeah, I honestly don't see buy in from anyone who already has a low overhead API happening.
Vulkan is likely to cover Windows, Linux (and related) and, as pointed out above, Android - although like OpenGL/OpenGL|ES before it I wouldn'e expect 'one code path to rule them all'.
Future landscape is likely to be;
MS platforms; DX12/DX11(legacy)
I'm intrigued, in a vague way, to see what happens with WebGL. It remains behind the times on features with everyone else in the GL ecosystem (iirc WebGL2 is still very much WIP) but exists in a world where Vulkan-like low level APIs don't really fit.
Although it's still very much a matter of 'when it happens...'; the other day the official VulkanAPI twitter feed posted a picture saying Vulkan was 'forged by industry', to which I replied along the lines of "forged by industry and AWOL. Less marketing BS, more specs/libs/drivers." because, for all the pretty slides, right now all we have to look at is marketing and one alpha Android driver.
(By contrast I've had a look over some D3D12 docs/examples, got a handle on the whole 'root signature' stuff and I'm making plans to write some D3D12 code on my Win10 system probably this weekend...)