User blog comment:Callofduty4/Why is it a sin for Treyarch to rip some aspects off of Infinity Ward but OK for Infinity Ward to rip off some stuff from Treyarch?/@comment-1503545-20100112123003

Because all these fanboys think that COD4 is the first Call of Duty game, and you are never supposed to say the people who made the first game ever "copies" things. Apparently, everybody copies from them.