"I personally found it rather dull and not scary, but then again I'm the type of person who doesn't really get scared by movies. I like horror movies that have twisted and crazy plots with lots of "twitch" factor to them. By twitch factor I mean a lot of parts where the killer/monster/etc. suddenly appears with a loud screech and the audience gasps and shivers from the surprise of it."
No offense, but I find that movies with sever "twitch" factor are poorly made, with no artistry. Anyone could design a movie like that, which plays off of a basic human response to something scary being thrust in their face.
Paranormal activity doesn't thrust itself into your face, it slowly worms its way into you, leaving you with a queasy, disturbed feeling that you can't quite shake. The acting is quite authentic seeming, while the plot is, perhaps, a tad simple. You'll really feel connected to the characters, and lets not forget, this movie cost less than 20 thousand dollars to make. You or I could have afforded to make it, but it really took a good director and talented actors to make us BELIEVE it.
Half of the theatre I was in were wondering if the movie was actually real footage (it's not, thank god, I had nightmares enough).
If you're looking to be disturbed and mildly terrified, disquieted and not just repeatedly shocked, then this movie is definately for you. If you want WOW-Factor and sparkling special effects, and blood and gore, then don't go see this movie. The horror is incredibly downplayed, but very cogent.
It wasn't the best movie I've ever seen, or even close. But was it worth going to see? Hell yes.