Is it improper etiquette to ask your opponent what his/her rating is before the game? Suppose you're playing in a tournament. For the purpose of filling up your scoresheet, is it improper etiquette to ask your opponent what his/her rating is before the game?
Yesterday, I played a tournament match, and at the table next to me the guy asked his opponent for his rating. “I don’t really know...” was the reply, “about 1580, I think. And yours?”

“Euhm... about 1400”, the guy mumbles in reply.

If you don’t want to give out your exact rating in reply or you don’t know it yourself, I would not ask the question to begin with. Furthermore, I thought the question was bad etiquette and would not really be happy with my opponent asking it.

Finally, where I live, most tournaments have lists of all participating players and their rating which you can look at. So start the game, and then after a couple of moves, when your opponent is thinking, you can always go check the list.

PS: I find that I play better when I don’t know my opponent's rating. Once I know his rating is a lot better, I get nervous and consider myself lost from the start. When I know his rating is much lower, I tend to play reckless and make mistakes.