Officially they say he died of heart trouble, but because of the fishy nature of his death and the fact that everyone aboard was sworn to secrecy, not to mention a couple of the ladies ended up on the payroll of Hearst, many thought he was accidentally shot and killed by Hearst himself. Rent the movie if you haven't seen it, again while not the best quality cinema it's still entertaining.
In any case, back to "After You've Gone". I really loved this tune playing during the closing credits, and turns out it was Kirsten Dunst herself who did the vocals for this version. Very nice set of pipes she's got! I ended up searching more about the song and came across this AWESOME cover done by the great Fiona Apple. She totally makes the song her own, I LOVE IT!