NEW YORK (Feb. 1) - Let it begin: the countdown, the party planning, the predictions, the meaning of it all. The tears - for the end of Harry Potter.

The world's most anticipated book finale, "Harry Potter and the Deathly Hallows," will come out midnight, July 21, according to author J.K. Rowling and her British and U.S. publishers, Bloomsbury and Scholastic, Inc. Ten years, and a few hundred million sales, after the first Potter book was released, Rowling will wrap up the magical adventures of the boy wizard, his friends and his enemies.

The author posted a brief announcement on her Web site Thursday, followed soon by releases from her publishers.

The news landed like a silent meteor. "Deathly Hallows" almost instantly topped the best seller lists on Amazon.com and Barnes & Noble.com, displacing another industry titan, an Oprah Winfrey pick, Sidney Poitier's "The Measure of a Man."

Potter readers, who had speculated the book might be published July 7 (7/7/07 for the seventh book) or July 31 (Harry's birthday), posted dozens of ecstatic messages on the Potter fan site, www.the-leaky-cauldron.org, within minutes of the announcement.

"OMGOMGOMGOMG!!!!!!!!! I CANNOT BELIEVE THIS!!!!" read one typical message.

"WAH!!! I think I'm going crazy!!!! We finally have a date!!!" added another fan.

Other comments were sadder, noting the series' conclusion.

"I can't wait to read the book, but at the same time, I'm afraid to read it," read a message from a fan named Christine, who identified herself as a "30-something" mom. "I can't stand the thought of anything happening to the characters that I've grown to love! What an odd feeling."

Christine and others have a lot to look forward to - and to fear. Rowling's stories have darkened considerably since the first release, "Harry Potter and the Sorcerer's Stone," and the author has said two characters will be killed off in Book 7.

"I don't always enjoy killing my characters. I didn't enjoy killing the character who died at the end of Book 6," Rowling said during a reading last summer at Radio City Music Hall, declining to name that person in case someone had yet to finish the book.

"I really didn't enjoy doing that but I had been planning that for years so it wasn't quite as poignant as you might imagine. I'd already done my grieving when I actually came to write it."

Rowling left millions sobbing at the end of Book 6, with a death and Harry's decision to take on the evil Lord Voldemort. Other cliffhangers for the faithful:

Who is R.A.B., the mysterious person who took one of the magical items Harry has been searching for? And what did he do with it? And where are the other ones?

Will Harry and Ginny ever be able to be together?

Still more unanswered questions: How many copies of "Deathly Hallows" will be printed and how many pages does it run? Judging from the suggested cover price, a meaty $34.99, $5 more than for Potter 6, "Harry Potter and the Half-Blood Prince ," the last book will likely match or exceed the 600-plus page length of previous releases.

"We have held the price for the past four years," Scholastic publicist Kyle Good told The Associated Press. "In that time, costs of production, paper, trucking, gas and security - to be sure all readers can enjoy the book at the release time - have all increased."

Fans can pay much less for "Deathly Hallows." Amazon.com announced that it would sell the book for $18.89, a 46 percent discount. Barnes & Noble.com offered the same price, but only for store members. Price competition has been so intense over the years that many retailers have acknowledged they don't make money on the fantasy series, depending instead on customers buying other books along with Potter.

Since Rowling first introduced Harry and his fellow students at Hogwarts to the world 10 years ago, the books have sold more than 325 million copies in 64 languages, broken countless sales records and shattered assumptions that young people, especially boys, don't like to read. Harry Potter and the Half-Blood Prince ," published in 2005, had an announced first U.S. printing of 10.8 million copies and sold 6.9 million copies in its first 24 hours.

Four hit movies already have been adapted from the Potter books. The fifth film, "Harry Potter and the Order of the Phoenix," is scheduled to come out July 13, just eight days before the release of "Deathly Hallows."

Associated Press writer Deepti Hajela contributed to this story.

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