The LA Times has an interesting article on how CRASH won Best Picture.
No crazy conspiracy theories here, just careful research and marketing by Lionsgate, who treated the race for the Academy Awards' top bauble like a political campaign.
CRASH won, the article asserts, because the right people saw it, specifically LA-based actors and editors, two key voting blocs.
The network effect also comes into play: Paul Haggis and the movie's large cast have been in the business for a long time, with associated relationships and friend-of-friending.
Relationships alone won't guarantee a vote, but word of mouth is perhaps the most powerful type of marketing. I'd wager that World of Warcraft is the first of such games for many millions of its players, who got into the game because a friend recommended they try it out.
Of course, no one's going to vote for a movie they think is terrible, even if it is set in LA, highlights actors, and a friend recommended it. Lots of people didn't like CRASH, but lots did, and Lionsgate made a strategic effect to connect to those lots.
Those 130,000 screeners, a joke in some circles when they came out, seem much less foolish in the cold hard light of post-Oscar March. The CRASH DVD was at #3 on Amazon when last I looked.