I have an Xbox 360 and a US, NTSC region Wii.
I've had the 360 for 2 years and haven't bought a new game in that time. I got it with Lego Star Wars, PGR3, Viva Pinata and PES6. As you can guess, it's mainly for my kids - I don't think I've played it for over 6 months, apart from helping my younger lad get his way through menus and things...
I think it came with GoW 1, which I played for about half an hour before selling. My problem is that I played far, far too much of the original Doom and Wolfenstein in the early 1990s and it's burned me out from FPS games like that. Also, the controls are too complicated for my elderly brain to deal with.
We only got the Wii for Christmas so the novelty value hasn't worn off yet - playing Mario Kart, Wii Sports Tennis, Mario & Sonic olympics, and occasionally some PES8 and Super Mario Galaxy.
So, strictly speaking not a COD4 fan, sorry.