This is going to explode into the next Leguna-style thread...I can just feel it.
I'm an avid keyboard + mouse player, and I hate the feel and inaccuracy of dual analog sticks to the point that I DO avoid console FPS games at all cost. I didn't play Halo until it came out on PC, and the same will be true for Halo 2. I would hope that the aiming accuracy would be beyond discussion at this point, but I also think that keyboard control isn't a negative for most games. When you're deathmatching, when exactly would you ever choose to walk? Even running isn't usually enough -- it's all about dodging, dodge-jumping, double-jumping, and misdirection to stay alive. If you're stuck in a platforming section in a FPS game then MAYBE analog sticks might be nice...but those aren't the games I usually play.
What I REALLY want to hear about are the guys who play with keyboard plus some other kind of peripheral on the PC. I have a good friend who uses a trackball (and is a wickedly good FPS player), and I've experimented with using a Wacom pad instead of a mouse, to poor results.
DopeyFish, I don't remember specifically playing against you, but I DO remember playing Tre', and if he says he kicked your ass, he's probably right. He's a skilled player.
As for anyone else looking for a UT2k4 game, I will try to remember to leave Xfire running (jinx90277) when I play...usually DM, though I'm trying to experiment with Onslaught too.