This piece by Marion Nestle in the San Fran Chronicle about what it means these days for a food to be labeled 'organic'. I especially like the article because it is in q + a format and is very simple and digestible (pun intended).
Check it out; you may learn something.
"USDA organic rules are about the letter of the law, not its spirit. Food marketers, however, take advantage of public perceptions that "organic" implies spirit - sustainability and better nutrition. Companies that follow the rules can legitimately market highly processed foods as organic, taking advantage of their health aura to command higher prices." -Marion Nestle