Well I just got "banned from matchmaking" due to "quitting". I quit a couple of games not knowing that it could get you banned (why should it?), so a message popped up saying if I did it again i'd get the banhammer. So I said ok, I won't again. Then I'm playing CTF about to capture and my teammate keeps shooting me, so I, forgetting that I can insta-kill with the flag, melee him, he boots me from the game and then I get a lovely message saying, "player has been temp banned from matchmaking on xbox live due to quitting"
Sure, someone quitting a game can be kind of annoying, be does that really warrant on ban from playing at all? Also, what if you accidentally teamkill? That makes it ok for the person to hit x and boot you from the game? I've accidentally done it before, but this guy decided to boot me. So in result I can't play multiplayer for who knows how long. Thanks Bungie.