It's with the gameplay, of course, and Quake III: Revolution
delivers a whole lot of solid gameplay. The lack of multiplayer support (silly Sony!) definitely hurts the game, and the load times are a pain too, but once you get down to it Q3R
is one of the most enjoyable console shooters out on the market.
I could tell you some plot, about trying to go up in the ranks of the Vadrigar's challenges and other nonsense, but it's well and truly irrelevant to the game at hand. There are two main modes of play: a single player campaign, where you pick a character and take them through the various tiers of the tournament, and the 'Arena', where you pick a place to combat and get some friends and duke it out.
The campaign is considerably more of a game than the campaign in the original Quake III: Arena. For one, the various characters that you pick are genuinely different. Every character has four stats, representing their speed, damage, health, and so on. Each character has a different mix of these stats, and different maximums for them as well. After you pick a character, you're stuck with them for the rest of the campaign. As you play and progress, you gain awards, and when you complete a tier, you actually gain stat points. Depending on how well you do, you get more or less points for your stats.
The important thing is that the stats are noticeable, and they are. I played as Anarki at first, and he was psychotically fast compared to the other people, and only got moreso as the game progresses. Sarge is nowhere near as fast, but he deals a lot more punishment to make up for it. You can pick a character that suits your gaming style, and stick with them.
The campaign itself consists of the same tiered mechanism as the original. Along with deathmatching, you'll do one-flag CTF, and an interesting game called 'Possession', where you have to hang on to the flag for a certain amount of time to win. Because of the lack of serious multiplayer, however, there's no real team play.
If you tire of the single-player campaign, you can play Quake III: Revolution with your friends. The game supports up to four people at once playing split-screen, and it works surprisingly well. Of course, even with four people, CTF is nowhere near as populated as it needs to be, and the bots can only do so much. Straight out deathmatch or the new Possession mode are entertaining, however, and you can have plenty of fun tearing up your friends in these modes. You can also use your characters from the campaigns, which is a nice touch.
But the important question is: just how different is it from Quake III: Arena? The answer is: not much. Some weapons from Team Arena made their way into Q3R, and there's a couple of new game modes, but for the most part the game's the same one that we played on the PC. So don't think that this is a whole new experience; think of it more as a refinement.