Sixaxis, Assassins Creed (looks and plays much better on PS3), Grand Theft Auto IV (looks about 2x as good as 360 Elite), new FF, Blu-Ray capabilities
VS. Wireless XBox controller, Halo 3 (and possibly a new Halo game), and by the way, does anyone know if RE5 is going to be PS3 exclusive? Probably not. Well I know you didn't want a specs or games list but this is just a rough comparison of what comes off the top of my head as a person in the same position as you, who owns neither console. Personally, I like the PS3 alot better but I agree with
russ in that the XBox controller is more modern and sensible; but you still gotta love the Sixaxis.

. After all is said and done, it's your call, friend.
I'm not your friend, buddy!
I'm not your buddy, guy!
Jam it back in, in the dark.