Ian Gavan / Getty Images Author JK Rowling.

Maybe you were watching that other debate, I don’t know. Your time is your own. As for me, I spent last evening at the David H. Koch Theater at Lincoln Center in New York City watching J.K. Rowling and Ann Patchett talk about Rowling’s new novel The Casual Vacancy.

This was Rowling’s only live appearance in the U.S. for the book, and the mood in the hall was giddy. These weren’t casual fans: there wasn’t a lot of actual Harry Potter cosplay visible, but you could tell a lot of people were cosplaying in their minds. I was a little surprised that some of the upper balconies of the hall were empty — I’d envisioned this as a bit more of a mob scene — but apparently the venue had been changed, after they accidentally oversold a different hall. The Koch Theater holds 2,586 people. Rowling signed everyone’s books last night, and that would have been a lot of books to sign.

(MORE: Lev Grossman’s review of The Casual Vacancy)

Rowling got two standing ovations, once when her name was announced, and once when she actually joined Patchett on stage. If you’ve never seen Rowling in person, you should know that it’s a bit special — she’s one of those people who, without having obviously been media-trained, has the trick of being smart and warm and natural and vulnerable-seeming onstage. She laughs a lot and makes fun of herself. She swears at the rate of about once every five minutes. She wears amazingly high heels. She’s a pleasure to watch.

She and Patchett, sitting facing each other with a huge Casual Vacancy book cover behind them, went right into the technical stuff about the novel’s composition. “The challenge was the structure of the book,” Rowling said. “I had a complicated diagram — arrows going in all directions.” (If you haven’t read the book, or the reviews, it’s a kaleidoscopic sort of novel with lots of points of view and many moving parts.) She works on a MacBook Air (“the MacBook Air changed my life. I can now work really anywhere.”) She had to cut out a lot of things she loved, including an autopsy scene, but as she said several times, “we are ruthless people, writers.”

It was a big change for Rowling, a real gut-check, to write a book that was this adult, with drugs and death and sex and even rape. “The first couple of people who read it, the immediate reaction was, ‘fucking hell!’ It’s so dark, it’s just so dark,” she said. On the other hand, she pointed out, the sex is not gratuitous — it’s not porn — which led to the obligatory 50 Shades of Grey joke, which was in fact the line of the night: “People have sex in this book, but nobody really enjoys it. That’s the difference.”

Rowling didn’t stay focused strictly on The Casual Vacancy. She and Patchett spent some minutes on the question of children’s books and why they’re important. “Children are very familiar with fear,” Rowling said. “And children’s literature gives them a place to explore that.” (Rowling also quoted, with a horrified shudder, an ‘expert’ she saw on TV: “‘Children must be protected from their imaginations.'”) They touched on Patchett’s second career as a bookseller (Patchett’s first career is as a bestselling novelist in her own right — Bel Canto, last year’s State of Wonder, etc.) Apparently backstage Rowling had been talking about how wonderful it must be to run a bookstore. “The minute you left the room,” Rowling says, “my husband said, ‘Do not open a bookshop! We haven’t got enough going on?'”

(Personally I think she should open a bookstore. Rowling’s husband, a doctor, was sitting in the front row, and they stopped at a couple of points for a little banter, but you couldn’t see him, or hear him, from Row S in the orchestra.)

(MORE: J.K. Rowling: More Harry Potter Possible)

Rowling was very funny, and quite touching, about her memories of the years she spent on public assistance, and on the difficulty of writing, and the insecurities that plague writers, even wildly successful ones. “We are thin-skinned people,” she said. A few times she mentioned the famous question of the Marauder’s Map, which caused her no end of trouble in the Harry Potter books. “My husband was the only one who never asked me why Harry had the Marauder’s Map back when it had been confiscated” (this plot-hole appears, if memory serves, in Goblet of Fire.) Later she remarked: “that map told you way too much.”

She and Patchett spent some time analyzing Fats, an adolescent boy who may be the most complicated, subtly drawn character in The Casual Vacancy. Fats is virtually amoral, but he’s also magnetic — “I feel guilty that I like him,” Rowling said. “He’s cool.” Patchett and Rowling had a brief exchange over whether Rowling is herself cool. They agreed to disagree.

The closing minutes were given over to questions submitted in advance by the audience (apparently I could have done this, but if so I never figured out how; I would have liked to hear Rowling talk about the significant amounts of negative coverage The Casual Vacancy has been getting, and how she feels about it. But see, this is why it’s good that it was Patchett up there and not me.) There were questions about what she was working on next — something, probably for kids, was the answer. Rowling was asked where she would live if she could live in any fictional place. “I’d like to go to Meryton and cut out Elizabeth Bennett with Mr. Darcy,” she said, and she added, to wild applause, “I do still walk in and out of Hogwarts.” But Rowling’s final answer was Moonacre Manor, the setting of a novel that she loved as a little girl called The Little White Horse.

At the end of the night every single audience member was given a copy of The Casual Vacancy, which Rowling signed. I already had a copy, which I’d read, but the staff wouldn’t let me give Rowling my old, beat-up, dog-eared copy to sign — apparently the new copies we were given had shiny anti-piracy stickers on them, which I don’t fully understand, but I guess they ensure that Rowling’s signature is genuine, which is of course a good thing. (On balance I would have preferred a copy of The Little White Horse, but none were on offer.)

Rowling is a pro—she signed, I would guess, about one book very five seconds, but she gave good eye contact, and she managed to communicate a lot of warmth in that very brief interaction. “It’s like communion,” Patchett ad-libbed, and she was right. It was one of those debates where both sides won. If Rowling/Patchett were running in 2012, and I wish they were, they would have my vote.

MORE: J.K. Rowling and 6 Other Children’s Authors Who ‘Graduated’ to Adult Books