Though Infinity Ward and Treyarch are both behind one of Activision's most prominent franchises, Call of Duty, the two don't seem particularly close, and certainly not like teammates. If anything, they seem more like rivals. Here is what Infinity Ward Creative Strategist Robert Bowling had to say about their relationship during GameTrailers' Bonus Round:

"The teams are completely separate. And our design schedules and our design philosophies are completely different tracks. It's not like they might be leapfrogging in terms of franchise but the design state of mind from the teams at Infinity Ward and Treyarch are completely different. We don't work together, we don't collaborate."

He added later that "the teams are very focused on what we're doing and we really don't let what happens in another game impact that."

It seems that their paths would cross more recently, with Treyarch being responsible for Call of Duty: Modern Warfare Reflex Edition on the Wii. It should be interesting to see if that has any bearing on either company in the future.