I played it at PAX, it seemed awesome but as I told my friends afterward my main concern is the content. The included AR booklet seemed like it's about 30 pages or so and I had already "used" three of them in my 15 minute demo.
I have to say, the AR stuff is implemented really well (like, it felt like the "next gen" of AR), it had great atmosphere, and the Fatal Frame half of them game worked like a more accessible Fatal Frame.
But the content, man... I had a bad feeling walking away from the demo it would only be about three hours.
I love Dementium and that game only lasted slightly longer than this seems to, so it may be a buy for me, but I can see many others having issues with it. I hope the game does well, though. It's obvious a majority of development time was spent on polishing the AR aspect and not on creating content.