OK, maybe this is wishful thinking:

I was running a Jasper Arcade with an old 20g HDD. I finally up graded to a 60g since BB sent me $40 in certificates.

So I did the HDD install for COD:W@W. And strangely, it seems to me that my online-MP is less "laggy", and more specifically less "jittery". I just had one of my best session of games, and I am actually a bit rusty right now.