Everytime a battlefiled and CoD game come out they always seem to copy each other's storyline.
BF3 and MW3 take place during current times in modern cities
BFBC2 and MW2 had the same type of story, just different weapon of mass destruction
BFBC2:Veitnam and CoDBlackops both take place around the veitnam war.
Now though both do change plots and stuff they both start out the same.
Both started out as a WW2 shooter, then they evolved to modern times.
Both are fun, both have great features, both have a great franchise, both have a great history.