What's your personal preference for the Call of Duty series. The reasoning doesn't have to be logical; it's your opinion. It could be length of time played, most fun, least frustrating, etc, that ranks it for you.
For me, it goes:
MW1 > MW2 > BO1 > MW3 > WaW > BO2
Obviously, CoD4 will be most people's starting points to.
I didn't put BO2 in there simply because I haven't played it enough to rank it. The game is a lot of fun so far but there are a couple of things that need tweaking and I want to see what direction Treyarch goes in to fix these problems.
It's going to be hard to beat BO1 though.
Godspeed You! Black Emperor http://bf3stats.com/stats_360/mrkinkyelbows#360