In a refreshing change of pace from the usual rage mail and clan invites, I was on both ends of such messages while playing today. In one lobby, I got three bloodthirsties and four longshots for my M8A1 thanks to a teammate with a riot shield being a fantastic distraction. After two games on his team, I sent him a "thank you riot shield guy, you rock" message. He responded by sending me a smiley face and hitting me with a long-range tomahawk the very next game. Then, in a later lobby, I camped with a random sniper on Plaza and saved him from getting shot a few times. I got a bloodthirsty myself, and after I left the lobby, the sniper sent me a message saying "thx for the backup, helped with my gold DSR" and it warmed my heart.
So have you ever received (or sent yourself) a positive message like this?