Industry-wide sales of print books are expected to decline by one third between 2010 and 2015, from $21 billion to $14 billion, according to a presentation by Barnes & Noble at the Liberty Media investor meeting last week as reported by Publishers Weekly.  During the same period, sales of digital books are expected to increase seven-fold, from $1 billion in 2010 to $7 billion in 2015.  That would put over-all sales of books (print and digital combined) down less than 5% from 2010 to 2015. 
Barnes & Noble expects to increase its share of print books during that period from 17% to 20% due to the collapse of Borders and reductions in the number of book titles carried by mass merchants.  B&N feels its digital book sales will benefit from having in-store sales and service for the Nook, vs. Amazon, which does not have a brick and mortar service footprint.  B&N also has high hopes for digital newsstand, app sales, and its self-publishing tool.