The problem is, how do you tell people that he's gay within the novel without, erm, revealing that he's gay? Sure, the newspapers picked up on this story once bloggers found the story, but I would expect a vox pop of kids who have taken the book out of our library, say, would reveal that the majority of them have not heard this.

The closet in fiction is possibly even worse than the closet in real-life, although at least in fiction there's a chance that you'll be transported to a magical world of dominatrixes and furries. ;)