District 9 accurately depicts corruption and discrimination in our society. It represents concentration camps and apartheid, the aliens being the 'outcast' and the morally corrupt whites and blacks being much like 'nazis' and exploiters. Racism plays a major role in this film, not only by the whites who have no problem tossing aside rights of the aliens, but also the blacks (in District 9) who are constantly using and killing the aliens for weapons.
District 9 is very much a concentration camp in physical and 'psychological' aspects. The aliens are used for experimenting and killed just for the mere fact that they are aliens (and different from 'humans'). I found the main character, Wilkus Van Der Merwe to be much like Oskar Schindler -- both helping and putting his life on the line (although sometimes it was for their own selfish wants and needs) in order to help save and 'free' the aliens (like jews/prisoners).
I found the film to be very interesting, insightful, and inspirational in regards to human rights and overcoming discrimination.