UPDATE: I did this with the original BFBC2 smart config, not the new one dropped on 3-22-11. If you want the new BFBC2 smart as well without losing this config, replace another smart config with the v 2.0 BFBC2 (maybe one of the 17 COD ones out there?) =)
OK....after two hours, this is what I came up with while using the Killzone 3 single player demo tonight. I farted around with the Halo config a bit, but ultimately I think the BFBC2 smart config is easily the best one to modify. Here's my breakdown, which I think -- while not COD responsive-- is @#$% good considering all the funky accleration and so forth that comes with the title. I was tearing it up by the end of the night. Of course, feel free to modify as you see fit.
MX518 - 1800 dpi mouse
Max in game sensitivity on both X and Y in the Killzone 3 settings
Clone the BFBC2 smart (first version -- NOT the updated one!) and change the name to Killzone 3, of course!
Sensitivity: 30.50 / 34.00
Acceleration: -0.15
Remember when binding buttons, if you change it to the KZ3 "alt" config, you almost have the same button layout as COD. I changed my "use" key (B on 360 controller) my side mouse button, and that's used for getting ammo, climbing up walls with friends help, etc. L2 in this game is your cover mechanic and squat (there is no prone), so map accordingly there as well.
The cover mechanic is interesting because I like to lean, and it allows that (even though you're exposed a bit if you aren't careful). I never got a hold of a sniper riflle, so can't comment on how that works with this config. I'd think it'd work well since I was tracking stuff in the sky with this while ADS without issue.
Hip fire is huge. I didn't even need to ADS except on truly long range stuff. And the melee mechanic was pretty sweet to boot. My favorite had to be the double eye gouge.
This is 10x better than what we had with XIM1 on Killzone 2, so I'm a definite buy now. I can't wait to try this online once I buy the game. Lemme know what you think!