I saw Crash last week. Not having seen many movies this year, I cannot compare it with the other contenders that competed with it for the Oscars.
The acting was great, and so was the tautness and structure of the movie. It was a bit intense and draining to sit through, but in a good way, because it engages and disturbs constantly.
The movie is very analytical and does not take a stand, which is a good thing -- I believe it really shows it like it is for many people, not just in LA, but any metropolis in the world that has communities and sub-communities living in their own miniature ghettos.