First off, I'd have written a script.
Not only is the dialogue poor and the action predictable, but the film feels like it was written by a couple of visual effects guys.1 Some of its other problems:
- It begins with a little teaser scene, then jumps back 15 hours to introduce the characters (three of whom are visual effects guys!). Attention, movie people: If you want to start with the action, then stick with it and develop the characters as you go. If you want to build up to the action by setting the scene and developing the characters, do that instead. You can't start with the action, then build up to the same action. Lose the frakkin' preface.
- It's a horror film, so as you'd expect, characters don't act like normal people. "Ooh, let's wait half an hour after the first attack to turn on the news and get more details!" "Ooh, let's all take the elevator when we try to escape from the building!"2
- Even if you ignore the illogical logistics of the alien invasion (How'd they sneak up on Earth? How'd they know before they arrived they wanted our braaaaains?), when you find out their sole motivation (they want us for our braaaaains), it still makes absolutely no sense. The aliens looked good, though.
- Along with the usual tension created by characters having conflicting plans for survival, the writers also introduced extra tension between characters (based on relationship issues) for seemingly no other reason than it's what they'd been told they should do in their screenwriting class.
- You're given practically no reason to care about any of the characters, unless it's because you've enjoyed watching them in shows such as Scrubs (Donald Faison), Dexter (David Zayas), 24 (Eric Balfour), NCIS (Scottie Thompson), or Sweet Valley High (Brittany Daniel).
- And lastly, the reason we get to watch the invasion unfold from the perspective of these characters is not readily apparent until the very end of the film. I'll give you a hint: It's not because they happen to be filming it (a la Cloverfield) or because they're the ones who figure out how to kill off the aliens (a la Independence Day, Mars Attacks!). I could say more, but I don't want to ruin the ending for you.3
And then maybe — just maybe — I'd have added a plot.
1 It was.
2 Spoiler alert: Nothing happens in the elevator.
3 I'll let the ending do that.