J.K. Rowling says it might be two years before the next Harry Potter book makes it into bookstores. (AP)

First, the good news: J.K. Rowling, author of the phenomenally successful Harry Potter series, is hard at work on Book Five.

Now, the not-so-good news: The follow-up to the summer's 734-page Harry Potter and the Goblet of Fire will not be out next summer, and might not reach bookstores for two more years.

"I really want to take my time and just make sure that it's as good as I can make it," Rowling explained in a telephone interview. "I don't want to be running up against an artificial deadline. I'm working on it now, and I have no intention of taking a break."

With more than 30 million of the Harry Potter books in print, and with Goblet holding the record as the fastest-selling book ever, there's certainly no financial pressure for Rowlings to hurry up on the latest adventure of Potter, a teenage boy who discovers he's a wizard and goes off to the Hogwarts School of Witchcraft and Wizardry to perfect his craft.

"I could not write any more, and never have to worry about not having money again," the former welfare recipient declared.

But fans shouldn't fret. Joanne Kathleen Rowling is still very happy living in Harry's world.

"In an ideal day I'll work six to 10 hours . . . I'm fighting to get time to write. I do still write in longhand, and I get away from the house whenever possible. I use cafes like offices, with the added bonus of good music and someone bringing me coffee all the time."

Rowling was tight-lipped on details of the next book in the planned seven-book series. But she did let slide that she had written the final chapter of the final book "just for my own satisfaction. Really, as an act of faith, as an 'I will get here in the end.' "

By the series' end, she said, "you do feel a sense of resolution. You find out what happens to the survivors, to those characters who live through all seven books. I know that sounds very ominous. You get a sense of what happens to them subsequently."

Other hints of what's to come: Readers will learn why Harry returns to the home of the dreadful Dursleys every summer. "The Dursleys are in the next book, and there's stuff coming with them that people might not expect."

Also, Rowling said, Ginny Weasley - little sister to Harry's best friend, Ron, who's been nursing a crush on Harry for the first four books - "will play more of a role in Book Five."