Just the mention of her name, J.K. Rowling, had the audience screaming and on its feet.

The Harry Potter author spoke for just over an hour before a capacity crowd on Tuesday night at Manhattan's Lincoln Center in her sole US public appearance to promote her first novel for grown-ups, The Casual Vacancy.

Dressed in a dark skirt and dark sweater-blouse, Rowling chatted on stage with US author Ann Patchett, read briefly from her new book and also responded to pre-selected questions from fans. Rowling spoke before some 2,500 people, mostly women, gathered under the high, golden ceiling of the David H. Koch Auditorium.

Patchett, who has a wide following of her own, thanks to such novels as Bel Canto, warned at the start that she was not "particularly nice". But Rowling had nothing to fear. Patchett gushed like the most avid Potter fan as she praised Rowling for inspiring countless readers and told her how much she loved The Casual Vacancy, which has received mixed reviews.

It was a grown-up, writerly conversation, with a few obscenities thrown in and a brief detour into the latest phenomenon, E.L. James' erotic Fifty Shades of Gray. When Patchett criticized James' writing as inferior, Rowling replied, "But that's porn."

Rowling said she felt a special connection to adolescents because of their "vulnerability" and how they come to comprehend there is "evil in the world". Stories, she said, can help them explore their feelings.

Rowling also discussed the difficulty of structuring a book and how attached she becomes to her characters. She spoke up for traditional publishers and the editorial support they offer as she explained why she didn't simply self-publish The Casual Vacancy.

She didn't just change her subject matter when she took on the new book. She changed the process. Rowling observed that with her Potter books, she did not allow anyone - not even her husband, Neil Murray - to see the manuscript before she had finished.

"I find that discussing an idea before I've written it," she said, is a way to kill it. But Murray was allowed early glimpses of The Casual Vacancy.

"He was - useful," she said.

Rowling reaffirmed that she is at work on a new book for young people. No new Potter book is planned, but Rowling still has her celebrated imaginary world in mind. Discussing literary works she'd like to live in, she mentioned Jane Austen's Pride and Prejudice, then confided she also dreams of more personal territory, the old school of Harry and friends.

"I do still walk in and out of Hogwarts," she said.