Serious Eats - seriouseats.com

Eggs listed as "free range" from the grocery likely do not come from chickens who were allowed to roam freely and are often no better and/or the same as factory farmed eggs:

http://en.wikipedia.org/wiki/Free_range

"The U.S. Department of Agriculture requires that chickens raised for their meat have access to the outdoors in order to receive the free-range certification. Free-range chicken eggs, however, have no legal definition in the United States. Likewise, free-range egg producers have no common standard on what the term means. Many egg farmers sell their eggs as free range merely because their cages are 2 or 3 inches above average size, or there is a window in the shed."