Will Modern Warfare 2 affect Assassin Creed 2 and Left 4 Dead sales?

[Slimebeast]

Assassin's Creed II is extremely strong.

12 million lifetime. (7 million on X360, 5 million PS3)

If anything, it's Assassin's Creed II who will hurt CoD 6 because ACII comes out first and people will be busy playing it when CoD 6 comes out.