Almost everyone I've seen use the Oculus Rift puts the device down with a goofy grin on their dial saying, 'THEY HAVE TO PUT 'GAME X' ON THIS'! That game could be anything: Minecraft, GRID, Call of Duty, Proteus whatever. But one of the most requested would be DayZ, and now someone's got it up and running.
The above video features DayZ with the Oculus Rift and the MAG II Gun controller, which allows for separate head tracking and movement with the gun itself. I'm really keen to try out the MAG II in general, just to see if it helps ease motion sickness, but I think DayZ would be especially intense using the Rift.