They don't need a GOTY award...they sold millions more copies than any of the nominees, and millions of people are still playing every day. GOTY is a great way to market your game in the $19.99 bin in the summer (Borderlands 2 and Far Cry 3)...
Game Devs...you will never please all of these complainers...so just ignore them and keep giving the rest of us the games we like.
CoD is definitely the series I put the most hours into. However, it doesn't feel right to name it GotY though. For instance, I consider Black Ops 1 to be my favorite CoD but I gave my GotY to Red Dead Redemption which came out that same year. Last year, Skyrim took it.
It's like.... CoD is in a category of its own. If there was a Multiplayer GotY category, it would win every time.