Amazon's Kindle Reader cuts book shipping Book sales in the United States surged during the holiday season, but in a dramatic shift for the shipping world, retailer Amazon.com said this week sales of e-books for the first time surpassed sales of physical books.  Amazon’s peak in e-book sales occurred on Christmas day as gift recipients used their new Kindle reading devices to make purchases from among the 390,000 books available in Amazon’s Kindle Store. The Kindle electronic reader, which allows users to download books and other media from a variety of sources, was “the most gifted item ever in...