A week ago the CtrlAltStudio Viewer updated to version 1.2.3.42797 Alpha (Windows download link) and is now on par with Firestorm 4.6.7.
This version does NOT work with Rift Direct Mode. Also, you must have the Advanced Lighting Model enabled to use the Oculus Rift display.
Now that Samsung is selling their Gear VR (US$200), we may start hearing more about people using these headsets in Second Life