Objectively...

Rating: 7/10 (27 October 2011)

Cons: - a lot about it has been borrowed from other films (from specific scenes to ideas globally, to camera angles...) - takes a bit of a while to get into the flow - seems just a tad bit slow in parts - needs to be taken seriously and to be gotten into to avoid boredom, staleness and feeling like it's repetitive images and recurring footage and documentary/study oriented. So requires attention and playing along, explaining the disgruntled crowd and their criticism.
Pros: - well written - not a typical idea for the presence, a rather original take on the cause of the said paranormal activity - a frightening cause - well acted, believable in deed - overall buildup on the entire picture and ending climax really quite chilling - good management of the sound - unknown well managed, well interpreted, great concealed/displayed ratio.
All in all: could have been scarier. Not at all as scary as the hype suggests. Worth watching. Not a bad film at all.