I have plenty of experience with all 3 modes and I really like the Wiimote for FPS' because its the most realistic and takes skill to master. The mouse and keyboard is too good, anyone instantly becomes world's greatest sniper. Console controls are simply so terrible I don't know how anyone plays CoD on a console instead of a PC unless they don't have that choice.
Though the game itself was not very good I really liked CoD3's controls on the Wii. Is it hard to shoot someone while running with the Wiimote? Yes, and it's just as hard to do it in real life. Is it hard to shoot somone moving or hiding over 150 yards away with the Wiimote? Yes, and it's just as hard to do it in real life. Is it hard to shoot all 30 guys running at you from all directions with the Wiimote? Yes, and it's just as hard to do it in real life. Does the Wiimote generate some inaccuracy from pushing whichever button to shoot? Yes, just like pulling the trigger is one of the biggest causes of inaccuracy in real life. I served in the army so I can attest to the fact that those things are not easy in real life (I only shot plastic targets but the principle is the same, and never from front and back at the same time but that can be inferred from the difficulty of front alone).
What will need to happen is FPS' will have to be different for the Wiimote just like they are different between mouse/keyboard and controller. Controllers require a dumbed down experience to mask their inadequicies, anyone who's played Halo on a PC can see just how dumbed down they are. Mouse/Keyboard requires huge numbers of enemies coming from all directions because again you can quite unrealistically drop somone at 300 yards while running and jumping with a mouse and keyboard. The Wii will need a more realistic experience. Not as many enemies, not as much movement (guess what, when bullets are flying all over you don't tend to move all that much), more emphasis on tactics and smart play like suppressive fire, flanking, bounding movement, proper use of cover, etc. All of that is generally pointless on a PC or console since both encourage Rambo tactics for different reasons (exceptional aim and movement on a PC and superhero stamina on the consoles).
I'm really excited about the ability of the Wii to generate realistic shooter games in the future. Otherwise I'd rate the Wiimote inbetween a PC and console. Preferable to a console FPS but since I have a computer I'd rather play CoD and MoH on it.
