Quake 2 was a very good game. Quake 4 follows on from that game. By now though PC's are a bit snazzier and so Quake 4 makes the most of this with its most redeeming feature - it's graphics. They are pretty impressive. Unfortunatley the same can't be said about the rest of the game. 'Mediocre' would be a more suitable word. There is absolutely nothing new here at all as far as I can see. If you've never played a FPS game before you'll think its amazing but if you played all the big guns in this genre then you'll be bitterly disappointed. The sound is OK, the weaponry is standard FPS stuff, and the action isn't really exciting, and the bad guys are not scary.
All in all, every aspect of this game has been done a lot better elsewhere.
With the likes of DOOM 3, The Suffering, Call of Duty, or even Painkiller to choose from why bother this this? Very average.