I think I was one of only about 4 women in the theater, which was pretty full but not packed. I strongly suspect that most of the guys were there for the special effects and people going boom - both of which were definitely present in the film - but were given a heck of a lot more.
I went into it not knowing a lot. I knew the general outline - aliens in South Africa - and that there was a lot of buzz surrounding it, but not much else. But even knowing just that little, I knew that there would be a lot of social/political aspects, given the country's history. All that was there, and a lot more.
I really liked that the main character wasn't (a) the perfect, PC guy just trying to do what's right or (b) the hero with a tragic flaw. He was just a guy, and a pretty weak one at that. He's casually racist, as are many of the characters, but not a bad guy. He loves his wife. He got his job because his father-in-law gave it to him. Throughout most of the movie, he's trying to do the right thing; but as the movie progresses, what he understands the right thing to be changes.
Really, such an original movie. I don't think this movie could ever have been made in the U.S. for a lot of different reasons, and it certainly would not have had the same ending.
Overall, definitely worth seeing. Even with the exploding people.