I don't usually give spoiler warnings but that seems appropriate here.
Jennifer's Body (Karyn Kusama 2009) - The common perception of this as a failed Megan Fox vehicle is likely due from people who haven't actually seen it. The film creates a context for Fox's limited acting abilities just as Terminator did for Schwarzenegger's. But it's also a clever take on high-school horror that successfully balances the grim (a high-body-count fire) with comic (an indie rock band trying to perform a Satanic sacrifice). The film also satirizes cultural obsession with tragedy and its ready-made "healing" narrative but almost obliquely, perhaps the best way. And like the best horror films (though this isn't quite to that level) it has an increasing sense of playing for keeps. (Odd that it ends with nearly the same shot as Paranormal Activity - a young woman who's just had a brush with a demon looking knowingly into a video camera.)
Drag Me to Hell (Sam Raimi 2009) - It's not a surprise to find out that the script was originally written around the Evil Dead period - it has that same mix of energized horror tropes and gross-out comedy. Or course that doesn't seem quite so clever now, making Drag Me the equivalent of a rock band covering "Louie Louie" or "Wild Thing" - fun but that's about as far as it goes. The ending bothered me for some reason. The twist with the coin envelope was well-done and since Raimi put it in plain sight I think most of us feel if we were paying closer attention we would have predicted it. But that's probably the mark of a good twist ending. However why end up with the protagonist, well, dragged to hell? Horror films do traffic in a sense of an unfair universe (though typically personified in malevolent beings of various types) but this ending seems extremely disproportionate to what she did originally.
Zombieland (Ruben Fleischer 2009) - Starts as a pretty decent comic zombie film, perhaps a bit too heavy on the "rules to survive" but not to a harmful extent. Then it starts to feel more and more tossed off until the final sequence in an amusement park that's about as mindless and hollow as anything I've ever seen. If it had maintained the opening tone nobody really would have cared that the film has an apocalyptic event with no apocalypse - months later the electricity is still on, food supplies are available and roads across half the country are easily navigated. And of course a country of 300 million is now apparently just 300, zombies included. But when the film gets too bland that's what stands out. The filmmakers really should have watched Dead Alive first.
Paranormal Activity (Oren Peli 2007/2009) - Maybe this would have benefited from a studio remake as originally intended. What we actually get has a decent idea, better-than-expected acting and not too much else. Even though it's aiming for a more classical approach of suggesting rather than showing there's just too little happening in the film. I kept looking for little things in the background or the edges of the frame but nothing there. The Blair Witch Project in a way showed even less but showing and seeing were the actual point - it was built around epistemology in a way that Paranormal only pretends to be. At first it seems like a strength that the film doesn't explain anything but simply presents us with a given. After a while when not much is going on it's hard not to wonder why the demon (assuming that's what it is) chose this girl and why when she was 8? Why wait this long, why do so little, why save a photograph and then years later stick in the attic? And why does the couple not close their door at night if there's weird stuff going on? The spookiest moment is the woman standing motionless for several hours at night and the ending does have an unusually effective jump shot. (There's a weaker alternative ending on the DVD that's much more conventional.)
Dead Snow (Tommy Wirkola 2009) - With IFC distributing this in the US you would think there would be something imaginative or inventive or simply well-constructed about the film but nope. Students in a snow-bound cabin, Nazi zombies - anything you can imagine is better than what we find in the film. You get a crusty local passing by who tells one story that of course explains the background. You get no phone reception, only one person who knows how to get back to the cars, zombies that at times seem mindless and at times smarter than the students. By the middle of the film it's almost like the filmmakers gave up trying to tell a story and just had stuff happen. I don't know how else to explain a film that is within-boundaries reasonably naturalistic but then has a guy amputate his own arm with no tourniquet and cauterizing on the equivalent of a candle flame, who then spends the rest of the film running (yes actually running) around without even becoming pale. We also have no idea why the zombies have waited 60+ years but decided now would be a good time to act.