Now, I've read the reviews here on Amazon and other film websites such as Rotten Tomatoes and IMDB. I fully understand the criticisms that have been said; it's not scary, nothing happens, it's too repetitive, it's boring etc etc etc. But I have to voice my own opinion on this one.
Having already watched the first Paranormal Activity and thinking that it was unique and creepy in its own way, I anticipated the sequel and was curious to how it would work out. You can tell that the film looks more professional than the first (I think the cameras used have been better) and on the whole it looks more polished, but you still feel the sense of it being recorded from an amateur style/point of view so it doesn't look totally Hollywoodified (if that's even a word). The film acts as a backstory to the main events that happened in the first film, but if you haven't seen that one the film does a pretty good job of explaining what is happening, and you don't really need to know much in hindsight anyway to understand it.
With a new film comes new cameras and surroundings. Since the film is taken place in a different house, the cameras record the outside pool, the hallways, the stairs, the living room and kitchen. In many cases you can see other parts of the house when one of the characters hold their cameras. What makes the film still creepy as the first is the eerie blue footage recorded by the cameras, combined with the film's skillful ability to create an abundance of tension. I like to watch horror films, and I've seen many before. You can't say that the film doesn't cause tension. I felt unnerved throughout the whole film, because like in the previous one, anything could happen. It uses dead silence and stillness so, so effectively, it feels like your holding your breath. As the film progresses though, it does feel as though you're just waiting for something, anything to happen. But that's really what the viewers of this franchise want. Nevertheless, they don't feel wholly like cheap scares, because the execution of the scares fit perfectly with the slow revealing of the plot and forthcoming build-up as the days and odd events progress.
Like the first film, the climax is definitely the highlight of the film. Obviously more things happen but it's a chilling and shocking end after the slow, momentous build-up created throughout the film. I think in this sense the film is still as effective as the first, and doesn't even show any blood, gore and other cliches in horror films to achieve this. It's said that the best horror films are psychological ones, and to a great extent it is true. In this case, the reason why the film is so undeniably creepy is that you never, ever see fully what or who is causing the paranormal events to happen. It puts more people on edge when people don't understand and see what is confusing them. Have you ever tried to scare someone? It's always the sound that creeps people out first, not the presence.
Granted, I wouldn't want to see this again since there is little incentive to after knowing the scares and having to anxiously wait for the build up. I think that this is not a film that everyone will enjoy or understand what to expect. It's not a typical horror film, like the first, but if you took the time and effort to watch this fully (due it its slow and fleshed out plot), it does manage to encapture the emotions and feelings you should get when watching a good horror film - it has to actually affect you, and it has to make you feel disturbed/anxious. Paranormal Activity 2 does that very well, albeit in an usual and slightly exhausting way.
I would hate to watch this film on my own, alone and in the dark!