I answered this to you yesterday :|
think enemy territory - bunny hopping class based shooting mixed with objective style gameplay
download TFC and find out - it should still be free
Enemy territory was a WW2 shooter and its free to download
The gameplay was fast and allowed for bunny hopping like quake.
The game type was objective based so that you had to build a bridge/blow up a bunker/defend a location etc.
The game was class based with dedicated snipers, troopers, demolitions etc.
TFC was exactly like this except the setting was more arena based and the soldiers looked modern but behaved like GRAVITY DEFYING MANIACS :E
Two teams, pitted against eachother in a war for flags. In most maps you'll be trying to steal your enemy's flag and bring it back. In some maps you have to control certain points by moving flags around, and sometimes you might even have to bring your own flag (or something that acts like a flag, such as a key) to a point in the enemy base.
Gameplay is oftentimes frantic. Grenades flying, shotguns blasting, conc-jumping, bunny hopping, explosions going off all around you, SGs hissing, chainguns wailing, scouts dashing, get the flag, run run run run run run run. Very fast-paced. Certain classes (or at certain times) you can play it slower, but more often than not you're moving at a breakneck pace (unless you're a heavy of course). Most of the time you're flying around the place; if you die, you respawn instantly, and you're right out the gate again back into the fray.
And while most games are played for flags, there are some other gametypes that offer a nice diversion now-and-then. Attack and defend maps, where one team must push up through a series of checkpoints while the opposing team scores points by stopping them. There's murderball, where there are four teams instead of two and one person holds a ball and scores points for his team, and other people try to kill him so they can get the ball. Hunted, which has one team as snipers trying to kill the VIP (a fat, umbrella-wielding man exclusive to this gametype), while bodyguards protect him. And if you're the kind of person who likes deathmatch there are deathmatch-style maps, and duel maps like Mulch_DM. Mappers can alter the gameplay in TFC radically, just through the map.
Like John said, download TFC and check it out. It's one thing to read about how it plays, another thing entirely to experience it in action.
Dark since you know a bit about it, do you know what those cooperative maps are? The ones where it's just one team that is trying to escape from somewhere, and there's AI enemies and puzzles and stuff to get through? Those are my favourites, but I can't remember what they are called.
Kamikaze beat me to it, but yep, escape maps. I think the most popular ones on those list that you'd have a chance of finding people playing today are colonyx_r and k_thegame. TBH I haven't played many escape maps, but those ones were pretty good fun if you had an organized team.