Just one day after the announcement that the seventh and last book in the Harry Potter series would be released July 21, Pottermania is raging once again, with e-retailer Amazon.com reporting record advance sales of the heavily discounted book.

The seventh title of the boy wizard series, "Harry Potter and the Deathly Hallows,' is so popular, that Amazon says it registered more pre-orders of the book on the first day than the 1.5 million books the company sold in the first two weeks of pre-orders for the sixth book. First day sales of the were up 547 percent compared to book six.

"Our customers have waited a long time for this book so it's no surprise to see them flocking to our site to pre-order it,' said Greg Greeley, vice president of books at Amazon.com. "Our customer discussion boards are teeming with excitement which we expect to grow in anticipation of the book's release in July.'

The company says that hundreds of thousands of customers had signed up for e-mail notices announcing pre-order availability. The book is priced at $18.89, 46 percent off the $34.99 retail price.

The advance book sales figures from Amazon could foretell a wider boom in retail sales for the seventh edition.

The sixth book in the series, "Harry Potter and the Half-Blood Prince,' which was released in July of 2005, sold 6.9 million copies in its first day on sale at U.S. retailers, according to 'Potter' publisher Scholastic. That edition has been called the fastest selling book of all time.