AP Programs (and Class and Race)

This guy suggested in USA Today last week that AP programs create a kind of class division among students, who are divided by their potential to go to college, and thus need AP classes:

All parents want their children to be with the nice kids, the bright and well-behaved types who will pull classes up, rather than with kids who will drag them down. In big, economically and ethnically diverse high schools such as mine, T.C. Williams in Alexandria, Va., where there is enormous variation in academic abilities, average kids run the risk of ending up in one of two tracks: in classes full of students with weak skills and lousy attitudes or in so-called advanced courses where they find themselves in over their heads.

All this AP stuff came about after my time (when I was growing up we all wore propellor beanies and kneesocks to school and said "Gee!" and "Golly" a lot, and then hurried home to churn butter and milk the cows) so I am wondering: do AP classes result in a kind of de facto (unintended) segregation of the kids by race or economic level because parents who expect their kids to go to college tend to themselves be of a certain class or race? What is your experience? Were AP classes exclusive or elitist, or were they diverse in those ways? Or what?