What does it mean to be "organic" for eggs?

It means:

• Poultry must be fed organic feed
• Egg producers cannot use antibiotics except in the case of an outbreak (no low-level antibiotics all the time
• Must pass basic animal welfare inspection (don't expect much from this)

This includes the fact that the chickens cannot be fed animal byproducts or genetically modified crops.

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