The Vermont House has just passed a GMO labeling bill by a heavy majority: 99-42.
This basically represents a state choosing to nullify the Monsanto Protection Act [assuming the Vermont Senate also passes it and the Governor signs it] by requiring labels that the Feds have said are unnecessary and may even be illegal.
State legislatures and referenda pushing back at the Federal government used to be derided as the province of "Tenthers" and conservative extremists.
But Colorado and Washington pushed back on marijuana legalization.
Twelve states have pushed back on marriage equality.
Vermont is now pushing back on food labeling exemptions.
For Libertarians this is pretty simple, doctrinaire stuff, trying to limit Federal power.
For our Green friends, who have consistently advocated for environmental and economic policies driven from the top down this may be new territory. "Think globally, act locally" may take on an entirely different connotation.