I don't know if any of you have played it yet. But it's insane. Much more tense and atmospheric than Slenderman, Outlast, even Amnesia. It's like if Groundhog day was a twisted, psychological horror. Obviously the game will probably have more to it, but the demo has made it a must buy for me. Play it with a headset, the sound design is awesome.
Or, if you don't want to play it:
Or, if you don't want to play it: