I don't know, maybe I'm the only one for whom AI has always been a non-issue. Programmers spend vast amounts of time scripting the AI to act "human" during the three second between when I see them and when they are a crumpled heap of pixels on the floor. In anything other than vast, outdoor type environments, the basic tactic is "see-shoot" with the occasional roll or dodge to impress the reviewers. There seems to me to be little difference between the best AI and the worst, provided they're not stupid enough to get stuck in walls etc (talking strictly FPS/action-platformers here).
In racing games, it's even more moot. I'm sure there are a thousand little intricacies, but when you're going 150 mph, trying your best to stay on the road, they don't really stick out. An adequately realistic script would be "drive really fast, go around cars/obstacles if necessary", though I admit I don't play too many racers.