to write the unwriteable wrong

I've heard this point discussed as well: having gay people or other under-represented people in your story, without making that the *point* of the story, is a Good Thing. It normalizes, it makes minority groups a little more mundane, a little more accepted. SF/F is a good medium for this, too: one can write a story with gay people in a society where they are not stigmatized; or a story with POC who haven't been oppressed because of their color (ie Teyla, Ronon, Teal'c, here). Which is fun and refreshing to read about or view.