I was just looking at someone's favourites over on Deviantart. One of them was some fanart of Starfire and Wonder Girl from the Teen Titans. The artist drew what I thought was a rather African-American looking Starfire, and the thought came to mind of Beyoncé playing her in a movie. And with that thought came the thought of the howls of indignation that would probably result in the dumber and, to be blunt, more racist section of comic book fandom. They would ignore the fact that Starfire, being an alien, doesn't fit into human concepts of race, and decide that the character is white. All one has to do is look at the idiot comments that came from some Hunger Games fans when one of the characters was portrayed by an African-American actress in the movie adaptation. Apparently the fact the character was described as having dark brown skin in the novel somehow eluded their grasp, and they thought she was a cute little white girl.
(Beyoncé would obviously be the wrong choice to play Starfire in a Teen Titans movie, being too old, but would be a good choice if the character was portrayed in a context where she was older.)