We watched Paranormal Activity over the weekend.
The characters were never really developed beyond “Reasonable Girlfriend” and “Jerkass Boyfriend”, and it opens with a few of the old fashioned loud noise/fake out scares that you might expect, but in the end it was a pretty effective little movie.
The nature of a faux-handheld camera movie frees you to not worry so much about character development, and the scares are well deployed and interesting enough to keep even a hardened enthusiast, such as myself, entertained.
Actually, in an odd way, it reminded me of Ju-on, the original version of The Grudge. Relatively simple horror stories, using relatively simple effects, each made more effective by their “home made” nature.