From a review of the new Jonathan Safran Foer book about vegetarianism in the Nov. 9th New Yorker:

Correction, November 4, 2009: The number of chickens currently being raised in the United States is nearly two billion, not four hundred and fifty billion, as originally stated.

I like that no one noticed this- I wonder how many chickens it would take to fill the US- can someone please do the math?