I really had a fun time with the game overall. It was a nice change from the puzzles of Thief and Deus Ex. You only need half a brain to play this bad boy, and you will still be satisfied with it. Serious Sam doesn't even pretend to be like the other games, it really concentrates on the action, and it shows. You will almost never run out of ammo, that's for sure. Every level has tons of health and ammo recharge points, and many of them even respawn. Unless you are totally incompetent, you will have plenty of destructive force behind you.
 

Graphics - Nice. The engine seems to be, correct me if I'm wrong, some kind of updated Q2 engine. The remarkable thing about the engine is the amount of enemies it can render at a time. Its not unusual to have about 20 guys on-screen at a time. Once, I had about 50-60! That was a massacre I'll never forget. All the baddies charging at you at once really instills an overwhelming fear in you chest, which is unique to this game.
Sound-The music is run of the mill, some old Egyptian-sounding techno. The bad thing about the sound, is the comments. Whoever did Sam's voice was going for a Duke Nukem-tough-guy kind of feel, but came up with a scratchy-voiced annoying feel. The comments made are also not clever at all. All Sam could come up with was a simple "Hey baby" when you get a gun. He also ruined the moment when the final boss, about 150 feet tall, came onto the screen crashing through buildings and being generally intimidating, by saying, "Your a bigot, ain't ya?" Talk about lame comebacks Sam. Maybe you could get some advice from Bill Cosby.