This game is good. No, just wait... erm... amazing? Extrodinary? I know *frags someone else* extrodinarily good!
It is impossible to play this game without getting shot, because you start off after every respawn (no wait, immediate rejoin) with dual assualt machine guns, but soon you will get the Scatter Gun and the almighty Link Gun. There are so many different maps, one of which set on a spaceship in space, allowing you to jump from platform-to-platform, gravity independant.
The only problem with Unreal Tournament 2004 the congratulations you feel after completing a kill, throwing your hands off the keyboard and shooting "Yeah, baby, yeah!" before realising that the match wasn't indeed over and getting shot repetatively in the face by the newb that doesn't understand you are celebrating a kill.
UT2K4 is a blend of Halo, Quake 3: Arena and any sci-fi game you have ever played, it's only con is that it has been modded so much, in some games people have been changing skins. Homer Simpson just fragged me, do'h! (-.5)