In a nutshell, Quake 4 just doesn't live up to its pc version, or any other games of the Quake franchise.
Single Player:
There is fun to be had in Quake 4's single player, but is it really worth paying 59.99 for? Absolutely not. There are a few memorable moments in the campaign, like manning a turret in a massive vehicle that is mounted in mid-air, and fully blown charging at a gate that is being protected by a smaller army of demonic aliens, but for the most part, the actual first person shooting parts of the game just really aren't all that exciting. Let's start off with the graphics. Bland, un-stylish, and very repetitive textures and visuals that make the PC version look like the God of all games, which is very dissapointing. There is a pretty good amount of weapons, but all of them are just lacking some kind of punch. For example, you will find a few massive machine gun looking weapons throughout the game, then you fire it, expecting loud, brutal gunshots, and instead, you get this quiet little hum and see some unimpressive, small gunshots going at an enemy. This dissapointment leads to the sound. The sound in the game, kind of like what I said about the gunshots, is very weak. Sometimes, you will hear a strong roar of your dying foes, but that's about as strong as it gets. Everything from your footsteps, to the moving of vehicles just all sound very underwhelming. Enviroments in the game pretty much all look the same, and the gameplay gets a bit repetitive, so you will find yourself putting down the controller quickly on this one.
Xbox Live:
Even outside of the box, the game is very unpleasing. Online multiplayer consists of only up to 8 players, which gets boring fast, considering most of the maps are too large to fit only 8 players in them. You will find yourself getting lost in some maps, not finding any opponents to battle for virtually, the whole entire game, until the time runs out. Overall, online multiplayer is unexciting and there is now way you should have to pay 10 bucks extra for it.
Conclusion:
Quake 4 described in one word is simply, boring. Almost everything in the game is bland and I don't see why the game is 59.99. In fact, I think this game should be cheaper than the pc version.