"Inglourious B*sterds" and "Hurt Locker" were better films, but "District 9", along with "Star Trek", is a movie that shouldn't be missed in theaters. Visually, this movie is a triumph and the cast is perfect. It definitely appeals to the sci-fi nerd in me and was reminiscent of many past films of the genre, including Alien, Aliens, Starship Troopers, King Kong, Enemy Mine, etc, but with the gritty, graphic (and more realistic) style of more recent war films, like Saving Private Ryan, Children of Men, and even the newest Rambo.
Don't have anything to say that hasn't already been said... definitely the best Batman movie ever made. I highly recommend seeing it at Imax if you can. I do wish they would do something different with Christian Bale's voice when he is in the bat suit ~ it's a bit annoying. It's a crying shame about Ledger. I could easily have watched another two and a half hours of his Joker.