Now Playing: 12-13-11 Marketplace

The FCC says it will regulate the volume of TV ads. A for-profit book recycling company collects books for charity, but then also sells them. The smog in China could cause economic delays. California's Napa Valley has a booming economy, but no middle class -- although education may soon play a role in changing that. Freakonomics Radio's Stephen Dubner talks about the hidden side of American food (and its bad reputation). And we look into what happened to the $1.2 million missing from MF Global's coffers.