HEADS UP ON AMAZON.COM GAY BLACKLIST HOO-HA:
After hearing from people on the inside at Amazon, I am convinced it was in fact, a "glitch."
Well, more like user error--some idiot editing code for one of the many international versions of Amazon mixed up the difference between "adult" and "erotic" and "sexuality". All the sites are tied together, so editing one affected all for blacklisting, and ta-da, you get the situation.
The CS rep who responded that this was Amazon policy was just confused about what they were talking about, and gave standard boilerplate about porn.
The dumbest part is saying it was a "glitch". A "glitch"? Just say that it was one of your workers making an editing error. Really dumb PR move, that one.