First off I will avoid saying too much about this film, because really everyone should go out and see it. As the movie hit its second act I was totally engrossed in the world of a South African reinstatement of an apartheid-like policy dealing with the aliens. It is probably my favorite movie of 09 thus far, (Avatar and Pandorum still coming though).
The Good: The down in the dirt style that South African director Neill Blomkamp weaves with his half narrative half documentary style. It feels like it was shot in a slum in South Africa.
This movie could only be spun by a gamer in love with Half-Life and Halo (which jacked a lot from half-life). For instance the Mech-suit (which can be seen in the trailer) is just like Dog in the Half-Life 2, but has a shit load of weaponry.
This guy knows how to tell a story with details. I'm sure I will catch a lot more in a second viewing, but you have to be able to appreciate the amazing amount of detail, which really brings an oppressed alien culture to life.
The Bad: The excessive use to military force was the real enemy in the film. Of course there is other stuff but I hate spoilers sooooo. That's all you get.
The Ugly: In this film the aliens are pretty ugly... But Blomkamp somehow puts you in the main character's shoes enough to where you kinda dislike them at first and think they are gross, but as the story moves you find yourself thinking the crustacean looking things are cute (especially the children).
The Badass: There is some all out battles in this movie. People get torn up by alien guns and human guns alike. There is one random part where this guy is holding an alien up for integration the alien out of nowhere just kicks him and all you see is a limb explode from somewhere and the guy fly like a rag doll. That is tame for this movie. Heads get torn off, lots of people explode, and many aliens get blown away too.