We already get Draw Notifications (if opponent accepts offer of draw). How about 'Your opponent has resigned' and 'Mate-u-lose' notifications aswell?
I know this would create extra email traffic, but it is nice to know when a game as ended on the opponents move.
I filter my games on 'my move' so often do not see that one has ended for a while and risk appearing rude for not sending a 'Good game, i'll kick your sorry behind next time though' type PM.
Just a thought... Andy