I like M. Night Shyamalan (well, I like The Sixth Sense, Unbreakable, The Village and Signs) and I tend to like the faux documentary/found footage movies. I liked this but, I don't think it got up to the level of his better films. I didn't feel the big build-up and the suspense that I usually get from a Shyamalan film - I think it tried and tried very hard to get the suspense level up but just didn't work at the level it really needed to.
There were some strong moments - but, ultimately the ending sequence wasn't quite long enough for me and felt rushed to me. The young lead actress gave a strong performance; the older gentlemen was pretty by-the-books but sparked a bit towards the end.