Still without giving any numbers, giant retailer Amazon.com says its third-generation Kindle eBook reader has become “the bestselling product” in their 15 years online retailer’s history. This is by outselling previous product leader ‘Harry Potter and the Deathly Hallows’, the seventh book in J. K. Rowling’s hit series.

Amazon has said its festive sales peaked on November 29, during which time customers around the globe ordered more than 13.7 million items—the equivalent of 158 items per second. Analyst Mark Mahaney, who follows Amazon for Citi Investment, noted the online giant’s busiest day this year represented a 44 percent increase from its best day last year.

Overall, online sales during the holidays posted a 15.4 percent year-over-year increase, with six days registering more than $1 billion in sales, up from three days in 2009. Retail analysts note that online sales account for only about 8 percent to 10 percent of total retail sales.

Amazon.com claimed that “many” people buying Kindles also own a tablet computer, which the retailer says they are using for games, movies, and Web browsing while the Kindle is favored for reading. Amazon said in a statement that iPad owners are also buying Kindles. The latest version of the Kindle is both smaller and lighter, a sharper display and a cheaper price tag at $139. This can also be cited as a reason for Kindle’s popularity among iPad owners. Also, though the iPad also has e-reading functions and the Apple iBookStore, battery life is significantly shorter than a Kindle, or other e-readers. iPads can handle only up to 8 hours of playback, while the latest Kindle can go for a month without charging.

The Kindle had stiff competition this year against tablets as well as other e-readers like Barnes & Noble’s Nook. However, it appears that Amazon’s strategy of marketing an inexpensive dedicated e-reading device, with an E Ink screen that preserves battery life and is readable in bright sunlight, was successful, at least from a sales perspective.

Barnes & Noble, whose highly discounted pricing for its popular Nook e-readers partially led to the bargain price of the Wi-Fi Kindle, has not revealed holiday sales figures. In related news, Stieg Larsson’s ‘The Girl with the Dragon Tattoo’ emerged as the holiday period’s most purchased book on Amazon, and also the most gifted Kindle book.

The Kindle currently has 47 percent of the e-reader market, down from its peak of over 80 percent before the iPad and Nook launched.

Via Pc mag