Alien Isolation... nice! I haven't started it yet. Maybe I should play it exclusively on the Rift to see how it does on a pure VR setup.
[edit]
Ok, update, it works really well. The intro & cut scenes are like being sat in a cinema (the video is projected in 2D), and the actual VR gameplay is definitely optimised for Rift DK2 experience - text is readable and the interface works very well. Walking down a corridor and seeing the steam trickling out of the vents is genuinely spooky. I've only just gone through the intro but it's certainly showing the best of what the Rift is capable of.
Best played with headphones!