Here's the
article from Hypable.com, which is a preview snippet of part of an interview that the Sunday Times is running tomorrow, which will appear in full in the issue of Wonderland guest-edited by Emma Watson.
I freely admit that a bit of me is reveling in the schadenfreude. Rowling's statements will forever blunt the "delusional" insult that has persisted since 2005, not even completely quieted by Rowling's half-hearted "it could have gone that way" comment in 2008. And the canon ships that were so clumsy that they looked painful onscreen and routinely made lists of "top screen couples with no chemistry" but were at least still canon in the books...now look that much weaker. Not even the author agrees that Ron and Hermione should be a couple. I do admit that a part of me grins at every canon shipper I see on Tumblr posting their wails and rage and denials.
A part of me regrets. Because if Rowling had stuck to proper literary alchemy as she began to do, if she had been brave enough to kill off Ron as the Red Death in the last book or at least not have him return (mind and spirit leaving the body behind in the final stages of alchemical transformation)...then the books would have hung together better rather than fall apart at the end and would have made a series that would endure for ages. But because Rowling stuck to an original outline in her head (an idea of Harry being raised alongside Hermione) but let her characters get away from her, showing the readers the natural closeness of the pair without any impression of siblings that the original outline would have supported...and because Rowling put her self-insert Hermione with the character based on a friend she probably had a crush on all through her teen years...what could have been great is merely there.
But mostly, I'm not sure what will change. I don't expect Rowling to re-write and publish a "definitive author's edition". The printed canon is still there. We'll see how much effect Rowling's admission of it not being right has outside of fandom.