We've already spoken about the possibility of Microsoft changing their DirectX API to be more like AMD's new Mantle API - bringing developers more access to the actual performance hardware. Now it looks they are going to be announcing a whole new iteration of the Microsoft API and not just an update.
A new Twitter account has appeared, called DirectX12 , and has teased an announcement set to take place at the Games Developers Conference (GDC) in San Francisco in a couple weeks time.
We've already heard about the Direct3D Futures and Evolving Microsoft's Graphics Platform talks from the information that's being sent around prior to the conference, but the only tweet out of DirectX12 so far links through to a static page teasing an announcement on the 20th March at 10am (PST I assume).
Information about what DX12 will mean for gamers, and crucially what operating systems will be supported, has yet to be released. From Microsoft passim though I doubt we'll see Windows 7 compatibility for DirectX 12, as the software creators have historically tried to encourage OS upgrades via locking down their new graphics APIs to the most recent operating systems.
Fingers crossed that it will still include Windows 8 and 8.1 and wont be hanging around waiting for people to make the move to Windows 9 next year. But I wouldn't put it past Microsoft. I'm also hoping this wont mark the return to the bad old, pre-DirectX, days where we had competing graphics APIs clogging the market and making PC gaming an even more complicated place to spend our leisure time.
The shining hope is that AMD have been behind Microsoft implementing the sorts of changes that they have been making in their Mantle API. If that simply becomes subsumed by the new version of DirectX I don't think AMD is likely to complain. After all, their hardware and driver teams have already been moving towards this goal and that may still give them a march over the competition.