I usually enjoy it when authors reveal extra information like that. Reason being, I don't want to clutter up a story with information that is valid but doesn't belong there. I mean, sheesh, what student thinks about their school staff as sexual beings? So of course Dumbledore's sexuality didn't come up in the story, but it's cool that Rowling knows what it is.

There are things about my characters that I know, but don't necessarily reveal in fiction or poetry. If people ask, though, I may answer -- and sometimes the discussion leads to another bit of canonical writing. That's especially prone to happen in my poetic series.