Although this film was intended to be a modern-day and comedic version of Guess Who's Coming to Dinner, IMHO, Guess Who played much more like an episode of "The Proud Family" cartoon. Bernie Mac's character, Percy Jones, seemed especially like the over-protective, nobody's-going-to-date-my-daughter cartoon father that Penny Proud contends with every Saturday morning on ABC.
Unfortunately, Guess Who barely touched on the racial issues. The jokes about racial difference were old and predictable. The funniest portrayal of the racial difference was the music playing while the father and the fiancée were riding together in a car. And in true sit-com fashion, all the issues are ironed out for a nice happy comedy ending.
If you don't mind paying a few dollars for a matinée show, it's not a bad way to spend a couple hours entertaining the children. Otherwise, I'd say skip it.