It's a fun game, there are just some hard parts. I played on medium and didn't find it impossible, just difficult. It has a realistic setting if you're really hardcore. It's more realistic than games like quake and unreal tournament, but not hyperrealistic like, say the Ghost Recon series or SWAT 4 (where if someone looks at you cross-eyed, you will die).
It's unlike other WWII-based FPS, in that you spend a lot of time creeping through the jungle looking to get the bad guys.
You are part of a team of 4 or more throughout the entire game, one of which is a medic. You can command the guys in basic manner (eg, covering fire, advance, retreat), and you can get healed by your medic a limited number of times per mission.
I thought it was well put together, although, I'll admit, I didn't like it as much as the original MOH:Allied Assault.