E-book sales grew exponentially in the first quarter of 2010, jumping
from just 1.5% of total US book sales in 2009 to 5% of the market in the
first quarter of 2010, said Kelly Gallagher, vice president of
publishing services at R.R. Bowker, who presented the findings of Book
Industry Study Group (BISG) research Wednesday during BookExpo America.

Source:

• http://www.booktrade.info/index.php/showarticle/27492
• http://publishingperspectives.com/?p=16286