Personally I can play consoles for longer, PC's are just a bit uncomfortable for playing games, the screen is small compared to a TV, and the extra hassles involved in PC gaming grate on my nerves.
With a console, you just slouch and play, everything is done with one controller in your hand, and there's really little chance of the game being ruined with a crash. For controls, well I always play console games differently:
PC: Aim with mouse, ducking in and out of cover with the keyboard.
XBox: Aim with both analogues, and move - the major factor being analogue straffing, use that to help you aim more accurately.
See the PC is missing a better movement control, I'd love to see a analogue joystick/paddle/gadget with a rotation control - vehicles could use the rotation to steer, but movement would be analogue and smooth. Best of both worlds I reckon. They could do so much with a basic joystick design for FPS movement, jumping, ducking, there has to be a better way than covering 15 keys with 5 fingers.
I just ordered a laser gaming mouse, it's so new I haven't seen it yet! (there are literally no images of it online anywhere) - 1600 DPI, the way I play BF2142, I think it'll make a big difference. What's a good DPI for a laser mouse these days?, 1600 sounds pretty good but I really have no clue about these things.
For the Xbox, your kinda stuck with the standard supplied controller, it's fairly precise, and buying a 3rd party console controller is usually a bad move - they just don't have the same quality. On the PC you can buy peripherals and gadgets till your blue in the face, and if your prepared to spend that extra on getting good stuff, then it'll be great quality.
For me though, the pinacle of console FPS has to be Halo, 2 player co-op with those massive controllers - I don't remember the last time a game hooked me like that, it was actually physically jaw dropping. IMO PC FPS games have a lot to compete with in Halo alone, the fun elements and co-op freedom is still un-matched. I mean, the first time you play Halo, you play it like no other FPS on PC or console, even though your health is very generously recharged, you still play it like it was your planet and life at stake - I REALLY got into Halo in case you can't tell
(completed it 2 or 3 times on EACH difficulty over the years). Halo2 sucked in comparison if you ask me.
''Stick that in your text and scroll it!.''