U.S. CD sales fell in 2006, but downloads were way up. No surprise there, but did you know that classical music was the fastest growing genre among all music sales? Chris Anderson, author of a book on niche marketing, thinks he knows why. “Classical is so badly served in traditional bricks-and-mortar music stores [that fans are forced to turn to downloading.] The fact that it’s one of the largest categories on iTunes, despite the demographic mismatch with the typical iTunes customer, is evidence that consumers are flocking online for choice.”