I have only played the demo of COD, but so far I'd say it is better in some ways but not others.
Pros- you have more control over what your game-person can do. You can lie prone, you can lean left or right, you can aim down the sights of your rifle (this slows you down if you are on the move), if a shell lands nearby you are stunned for a while (your movement and vison is impaired). YOu seem to be more limited in terms of what you can carry all at once. In these respects it seems more realistic than MOHAA.
Cons. The enemy seems more cartoonish than in MOHAAA. They tend to swarm over walls directly in front of you- they don't seem to act with as much intelligence as those in MOHAA. This really gets on my nerves with the demo. There is a scene where you defend a church with 2 or 3 MG s- the Germans just basically try to swarm up to the chruch in a frontal assualt not making good use of cover. They have mortors and tank support- but they choose to attack by a frontal assualt straight into the MG's. I guess it lives up to the claim of being "intense" but I'm hoping for soem improvments because if they fixed this aspect it could be a really great game.