So, according to the transcript at the Leaky Cauldron, Rowling says that Dumbledore if gay. She also says Neville marries Hannah Abbot and lives above the Leaky Cauldron (Hannah apparently takes it over when the current owner moves on). (I wonder if faculty for Hogwarts commute? Do they apparate into Hogsmead and fly the rest of the way?)
My problem is that while Dumbledore being gay doesn't contradict anything in the text, it also doesn't fit very well either. Sure, it's a YA book, and Certain Things are not discussed in a YA book. But I've had this problem with Rowling's work for awhile. I like them, and they have a lot of good stuff. But I never feel like more than 50 people live in the Wizarding World and I have no clue how it all fits together, how it's government works, how its economy works, etc. Contrast this with most Heinlien YAs, where he wrote under much more severe limitations and stricter editing. Even if I couldn't tell you precisely how things work in the universe of The Rolling Stones, or Podykane of Mars, or Citizen of the Galaxy, it always feels like there is a vast, teeming, fully developed and functioning world out there.
Similarly with Neville and Hannah. I mean, there's no reason why not, but there's nothing that suggests "oh yeah, that so totally makes sense." Even if Neville didn't end up with Luna Lovegood (which Rowling objected to in the past as being too pat), it would be nice to have had somewhere in the 7 books covering this something that one could point to and say "ah, now that makes sense." No, life doesn't work that way, but good literature generally does.
Overall, it's not a big deal. But it's consistent with why I think of Harry Potter as good and fun but not great literature or even great genre fiction.