Barnesandnoble.com has added an hourly, real-time Top 100 bestseller list and more than 300 category top 10 lists to its online store. It is the third time in as many weeks that B&N.com has introduced a new feature to make itself more attractive in a crowded and increasingly competitive marketplace.

The new bestseller list, drawn from both B&N.com and Barnes & Noble bricks-and-mortar sales, is being touted as What America's Reading. Its introduction appears to be an effort to draw attention from Amazon.com's popular hourly Movers and Shakers list.

B&N.com's new category top 10 lists come in a wide variety of fiction and nonfiction categories, from teddy bears to robotics. Additional "hot lists" are added each week, offering top 10 bestsellers in more timely categories, such as the June 26 posting, which added lists labeled Hail to the Chiefs (presidential biographies) and Bestselling Preorders.