E-book sales are skyrocketing, which is one reason why e-latecomer Borders is sitting in Chapter 11 while e-embracer Barnes & Nobles is not. According to the Association of American Publishers, a coalition of 300 book publishers, total books sales on all platforms, in all categories, hit $805.7 million for January 2011, down 1.9% from $821 million in January 2010. It also noted that January 2011 electronic book net sales increased to $69.9 million (8.67% of total), up 115.8% versus $32.4 million in January 2010 (3.95% of total). Meanwhile, all the myriad print categories were down anywhere from 2% to 31% except two — religious books and professional/scholarly books. Long-term prospects for the e-books look brighter by the year, but one category bears watching: the neither fish-nor-fowl ‘Downloadable Audio Books.’ Those January 2011 sales rose by 8.8% to $6.5 million versus January 2010’s $6.0 million.