From BashAndSlash.com:
"As you may be aware, our very own PST*Joker has made assertions on BASH that the MP AC130 and several other MW2 features were influenced (without any recognition) by him and other PC modders.
A few hours ago, I saw a Tweet go out from a community member suggesting that Joker issue a takedown notice of Infinity Ward's AC130 vid on Youtube. "
A modder from the Call of Duty 4 community has contacted Youtube and filed a copyright complaint against the gameplay trailer of Modern Warfare 2 from July 27th. This trailer featured an AC-130 which was part of a COD4 mod called X4 without any credit going to the creator.
Youtube has removed this video from Infinity Ward's official Youtube channel.
Infinity Ward's community manager Robert Bowling has this to say about it: "Really? Copyright infringment claim? :sigh:"