Depends.
How many of each will be available and if the MW2 bundle goes to Others.
However, taking a very rudimentary approach. FF13 means more in japan than COD means to America. When we take into account the size of the population COD has an advantage, but of sheer importance and or demand based on market size FF has an advantage.
The biggest advantage of FF13 is that its an exclusive game in Japan whereas in America people can get a PS3 to play it.
So all things considered id say the fact FF13 is exclusive and bundled will lead to more bundled sales.