And now Joe Creig writes to ask, "One thing I've never understood is why it's possible for a movie to be nominated for Best Picture but not for Best Director. Isn't the best movie the one that was the best directed?"
Answer: That may or may not be the case, but the real answer is that it isn't the same voting body in both categories. The Best Director is voted on just by the branch of the Academy that covers directors, whereas Best Picture is voted upon by the entire membership. So it's kind of like asking why a majority of voters in Arizona went for George W. Bush, whereas a majority of those nationwide chose Al Gore. It's a different roster of voters.