I don't know what's happening with iD software and Oculus regarding Doom 3 BFG. And I don't know when we get our $20 steam vouchers to help buy Doom 3 BFG.
But we've been working on adding Oculus Rift support to the source code, since it's open source (except the Bink video playback). Our Rift's haven't arrived yet though, so it's a bit hacky.
We've got head-tracking working, but we haven't fixed the shaders or rendering for the 7" yet. Head tracking should work for real Rifts or for Hillcrest trackers.
Download (old version):