Honest to God, when JKR starts talking about the books, I usually end up wanting to kick something because I often get the feeling she just makes up answers off the top of her head, and moreover treats her characters as symbols rather than people. I don't take interviews as canon in any way, and I think the central texts in the HP-verse will always be the seven books.
HOWEVER, this still makes me really, really happy. It's really important to me that not everyone in the Wizarding World is straight, and that she recognizes that, and that she's willing to say it publicly. The only conspiracy theory in the world of HP that ever made me squirm was when people started positing that JKR pushed Remus and Tonks together because they were both plausibly queer characters (they still are plausibly queer characters) and she wanted to reaffirm the heterosexual norm. I worried over that. (I had a seriously bad experience with Robin Hobb freaking out over her own subtext, okay? Ya gotta cut me some slack.) I still think Dumbledore's a jerk with some major control issues, but no one said gay people have to be perfect.
I was never one of the people who hoped JKR would put a reference to Remus/Sirius in canon. I knew it was there, and whether or not she knew it was there was fairly unimportant. There's no point at which the sexual identities of people older than Harry are central to the plot, and if they're never clarified, that's fine. I fully believe sexuality is fluid, and being in a relationship with someone of one gender does not in any way prevent you from being attracted or having been in relationships with people of any other gender. I also think it's really important that literature, particular literature read by young people, provide an example that not everyone in the world is the same, and not everyone has the same relationships. I want to see gay people in books (and it's always better when they're not just someone's wiseass sidekick), and queers of other stripes, and interracial marriages, and religious people, and atheists, and Jews dating Catholics, and people in wheelchairs. Insofar as a book is a universe and maybe not all of those people are actually visible, but I want to have the sense that they're just over the next hill, and that if they showed up to dinner, that'd be okay. I want literature for kids to be better than the world most kids live in. Literature for grown-ups could use a dose of this too.
Right, that turned into a rant. AHEM.
In conclusion, I think it would make me happy if JKR had outed any character because it confirms something about the construction of the Wizarding World that's really important to me. If there's one queer wizard, then I bet there are loads more, all over the world, snogging in broom closets, and getting married, and sharing awkward silences, and pining over people who haven't yet noticed how hot they are. Sometimes I'm so invested in literature, I even scare me.
Love all,
B&z