Good, but could have been better...
First of all, the single-player. I am sure anyone will agree that the AI is terrible. The only thing there capable of is having incredibly uncanny aim. You can sneak behind enemies and stay there for minutes without them realizing it, and there strategies are repeated over and over again. You can literally run up to a mounted machine gun net, kill the guy using it, use it for yourself, kill the next wave of soldiers that will always be your second objective counter-attack and come out completely undamaged. Also, the levels are uninspired, (usually, the mine fields are kind of intresting.)
My only other thing is the Wii gimmicks. Some of them, admittely, are good, like pumping the shotgun with the numchucks, or the mounted machine gun and mine detector concept. But things like putting the wii-mote on your shoulder to shoot the bazooka and moving an artillery with the nun-chuck are just aggravating. And don't get me started on the mortar.
Over all, it is worth the money you soent, but you have to play it with an open mind.