Yes, we're seeing news of this. Quite ballsy for folks to be taking hacked Xbox 360s on Live where they are detectable. In any event, we already have opened channels of communication with Microsoft on these issues Friday night. If you can capture screens or video of this in action (as some have already) we're working on bans for boxes and accounts with Microsoft for haxxors."It seems that Capcom have since dropped their request for assistance, saying simply: "We'll catch them ourselves."
via GamePolitics: http://gamepolitics.com/2012/03/19/capcom-says-it-aware-hacked-street-fighter-x-tekken-dlc-characters-being-played-xbox-live