I've been working on upgrading Mystfit's VR version of the Plasma client to work with the consumer version of the Oculus Rift. Used WineD3D to convert D3D9 calls to OpenGL calls.
The main problem (besides the fact that I'm incompetent in anything involving GUI stuff or teleporting, so there's a good chance of motion sickness) is that the Oculus SDK is not compatible with the GPL. Neither is OpenVR, the main alternative.
Just today, the preliminary OpenXR spec was released, and I could switch to using that, but there's no Oculus Rift runtime for it yet (maybe there will be soon?) and there's a good chance I'll end up getting bored by the time something's ready (should be this year).