From the July 30 interview:

Alicepie : What happend to luna, did she get married? who to?

J.K. Rowling: Luna became a very famous wizarding naturalist who discovered and classified many new species of animals (though, alas, she never did find a Crumple-Horned Snorkack and had, finally, to accept that her father might have made that one up). She ended up marrying (rather later than Harry & co) a fellow naturalist and grandson of the great Newt Scamander (Rolf)!

Katie Mosher: How is the quibbler doing these days
J.K. Rowling: Pretty well, actually. It has returned to its usual condition of advanced lunacy, and is appreciated for its unintentional humour.

From a slightly older interview (early July?):
The wizarding naturalist
Luna Lovegood, the eccentric Ravenclaw who was fascinated with Crumple-Horned Snorkacks and Umgubular Slashkilters, continues to march to the beat of her own drum.

“I think that Luna is now traveling the world looking for various mad creatures,” Rowling said. “She’s a naturalist, whatever the wizarding equivalent of that is.”

Luna comes to see the truth about her father, eventually acknowledging there are some creatures that don’t exist.

“But I do think that she’s so open-minded and just an incredible person that she probably would be uncovering things that no one’s ever seen before,” Rowling said.

Luna and Neville Longbottom?
It’s possible Luna has also found love with another member of the D.A.
When she was first asked about the possibility of Luna hooking up with Neville Longbottom several years ago, Rowling’s response was “Definitely not.” But as time passed and she watched her characters mature, Rowling started to “feel a bit of a pull” between the unlikely pair.
Ultimately, Rowling left the question of their relationship open at the end of the book because doing otherwise “felt too neat.”