Planet Money Podcast Looks at the Economics of Textbook Prices

The NPR Planet Money podcast spent a bit of time on the problem of textbook prices in the US.  I know that many folks here are concerned about textbook prices.  This piece, "Why Textbook Prices Keep Climbing", provides a pretty nuanced explanation of the problem.  As with many things, a big part of the problem is that instructors don't know the costs of the texts that they require and rarely select texts with pricing as a factor.