At her site I came across an essay titled Shame, by Pam Noles. Written by a highly intelligent woman of color, it talks about the continued and often seemingly ignored trend in sci-fi and fantasy to write from the white perspective. It was prompted by the Sci Fi channel's magnificent ability to cast what was a book filled with people of color as all white. LeGuin actually talked about their "whitewashing" on Slate when the miniseries came out.
I followed other links to find this freaky and sad gem written by Douglas Blaine... and before you go agreeing with his viewpoint (not that I think you will), read Tobias S. Buckell's refutation because every word he says is worth reading, and worth practicing.
Pam mentions Buffy in Shame, and again in her response to the responses.
She says, in the original essay:
Am I the only FoP [Fans of Pigment] forced to develop a veneer of denial in order to function at the gaming tournaments, at the conventions other than the comic book fest in San Diego, or while watching "Buffy" and wondering if The Hollywood People who had ever actually been to Sunnyvale? Because, you know, if they had, there'd be five Asian/Pacific Islanders and at least three Latinos in the background. Am I the only FoP who was reduced to searching the people in the background because the people in the foreground were always a given? Am I the only one to wonder why the Los Angeles of "Angel" looked a lot like the New York City of Woody Allen's films?
There's a fic of tabaqui and reremouse's where Gunn asks where the hell all the people of color are (it's called SNAFU and is Spander if you're so inclined) in Sunnydale, but most of the time I think people in the Buffy 'verse stick within the boundaries set out by Joss. And maybe that's too bad.