What can I say? I enjoy this game very, very much. I haven't truely enjoyed a FPS game which rank with the sort of Counter-Strike and Unreal Tournament. Others mentioned, how can a medic fly a plane or a scout driving a tank? You know what, I don't care. How many FPS games out there allows you to have complete control in air, land, and sea? Therefore, I have fun with the game, tons of fun, and that's all it matters.
One problem I find with the game is that you really need a powerful machine in order to get a good flow of the game. I used to own a 700MHz, GeForce2 machine (which is higher than the minimum requirement) when I first play the game and it really gets laggy, both single and multiplayer. I then upgraded my machine to 1.8GHz and a GeForce 4 v-card and the game really flows smoothly with my cable modem connection. This could be a problem to those who have slower connection and a less powerful machine.
Other than that graphics, sounds, gameplay are all top-notched, not to mention its addictiveness. I can't stop laughing when I shot down an airplane with just a mounted machine gun on top of the tank or blows up a ravaging tank with my bazooka. If you want a complete feel of how a real battle is, this game is definitely for you.