Listen there's players like TBNRfrags that have tweeted and keep suggesting they (AimBot) hack and when he tried playing MLG 0.50 KDR and after two game was out. IF you're seeing everyone in this video you'll forget you're playing with a Wall Hack.
Again, one short clip with one (1) WTF Kill means nothing, and I said IF you're doing frequent kills like the one in the video throughout the game Prior Ban(s) or not folks are going to call you out as a cheat.
Noob + Hack = MLG
You should see this post on my feeling of Prior Ban(s) Players -> http://community.callofduty.com/message/414599285; I noted your comment and of course you feel that way, but in my experience 80%+ with Prior Ban(s) are indeed cheating in BO2 - period.