UPDATE: The PBS episode "Food Machine" premiered on April 11th, 2012 on the series "America Revealed." Now the episode is available online.
"Over the past century, an American industrial revolution has given rise to the biggest, most productive food machine the world has ever known. In this episode, host Yul Kwon explores how this machine feeds nearly 300 million Americans every day. He discovers engineering marvels we’ve created by putting nature to work and takes a look at the costs of our insatiable appetite on our health and environment. For the first time in human history, less than 2% of the population can feed the other 98%."
Via Seth Dixon