Amazon launched a new version of it Kindle reading device, as well as a $139 Wi-Fi only version. The successor to the second generation Kindle still offers free 3G, as well as Wi-Fi, and is 21 percent smaller and 15 percent lighter (8.7 ounces) than its predecessor. Amazon claims the new device has 50 percent better contrast, 20 percent faster page turns, up to one month of battery life and double the storage.

On seeing content sales soar after lowering the price of the second-generation Kindle from $259 to $189, the company follows the new flagship Kindle with a $139 Wi-Fi only device.

“At this price point, many people are going to buy multiple units for the home and family,” said Jeff Bezos, Amazon.com founder and CEO, in a statement.

Amazon was recently forced into an eReader price war when Barnes & Noble slashed the price of its Nook eReader and released a cheaper Wi-Fi only version. In late June, Barnes & Noble introduced a $149 Wi-Fi-only Nook eReader and shaved $60 off its 3G model, bringing the price for that device to $199.

Amazon’s $139 Wi-Fi only version sets a new standard for the company as it begins to think of the eReader as a mass market device. Bezos recently has been insistent that his company is not in competition with Apple’s iPad.

“For the vast majority of books, adding video and animation is not going to be helpful. It is distracting rather than enhancing. You are not going to improve Hemingway by adding video snippets,” Bezos told The Wall Street Journal, adding that “there are going to be 100 companies making LCD tablets… Why would we want to be 101?”

The lower eReader prices have done wonders for Amazon’s content sales. The company recently announced that sales of eBooks had surpassed sales of hardcovers. Over the past three months, for every 100 hardcover books Amazon.com has sold, it has sold 143 Kindle books. Over the past month, for every 100 hardcover books Amazon.com has sold, it has sold 180 Kindle books.