ampillion on 03 June 2007
AI in of itself isn't all that process intensive, from what I've heard. It's merely coding, and the way it's streamlined and branched out to give the AI more routines. (Relaying from what others have said.) Handling many more characters on screen, each with their own complex AI, possibly. But AI lately in games has been abysmal at best. Physics and more screen activity is at least much more noticeable for the time being, there's games that show that off.
