The Tech Report reports one of the lead engineers and driving forces behind Valve's VR project has moved on to Oculus. Former Valve engineer Atman Binstock will take on the title of Chief Architect at Oculus and he will head a new R&D teamed based out of the Seattle area.
The defector is Atman Binstock, whom Oculus describes as "one of the lead engineers and driving forces behind Valve’s VR project." Binstock apparently put together the "VR room" demo Valve showed at its Steam Dev Days event last year. I don't believe that demo was made public, but according a story by Road to Virtual Reality, it was quite impressive:
I put on the headset and the first thing I noticed was the clarity and high-resolution, as compared to the original Oculus Rift developer kit. The refresh rate was extremely fast and I felt completely at ease looking around using the headset, with no nausea. Keep in mind I had already put in a number of hours on the original Oculus rift developer kit so I am fairly acclimated to VR experiences in general, but in talking to some others who had experienced this demo, it seems that the nausea level is greatly reduced with the new low persistence screens that are being used in both this prototype and the new Crystal Cove Oculus Rift headset.