Wanting to understand more about the Solow residual, I found this short MSNBC segment where Ezra Klein interviews Michael Greenstone, an MIT economist whose work deals with the relationship between innovation and economic growth. While it doesn't go into deep technical detail, I think it helps show the importance and immediacy of the concept. In addition, I'm intrigued by all the public policy concerns that intersect here--education, immigration, industrial policy, etc.