The survey is flawed in a number of places (as outlined in the article itself), but the information contained is very fascinating.
"In an industry without a lot of good news to report, the one consistent bright spot has been publishing for teens. While adult trade sales are expected to fall 4% this year, juvenile and young adult sales are expected to increase 5.1%, according to the PW/IPR Book Sales Index. Although it's impossible to completely break out juvenile from young adult (YA), it is possible to look at expected growth rates for different categories. In the fiction/fantasy/sci-fi segment, where most sales in the YA category fall, we expect nearly 13% growth in 2009, reaching $744 million. By 2013, sales in this segment are anticipated to hit $861 million, a 30.6% increase over 2008."This gem and more is found at What Do Teens Want?