I played the COD4 beta and loved it. Was waiting for that SEGA Rally demo but my 360 finally bricked - red ring of death! I say finally because 3 out of 4 mates have had theirs repaired under warranty as well.
There must be some serious design and/or quality control issues with the 360, but if you have to choose out of the 360 or the PS3, the 360 is going to give you better value in the long run. If/when your 360 dies just demand a loaner before you send yours back in. It will come back with another 3 yr warranty regardless.
And they come in black now, to match your B&O hifi gear.