Seems to be a movie you either admire or loathe. A lot of guys I talked to said it was too heavy-handed; I did not hear the same reaction from the women I know who saw it. It can be fairly melodramatic, but the dialogue was, IMHO, spot-on.
Me, I liked Crash for taking the chances it took, plus I have always loved intertwining stories and ensemble pieces. It was made for under 7 mil, I don't think the actors were paid too much upfront.
Crash also won for screenplay and editing, it's story is complicated, but quite fast-moving and tightly put-together.