I would just comment that there's no published evidence so far of negative health effects from the current generation of GM crops. There is certainly a series of studies out there about environmental changes that have occurred as a result of large-scale GM crop deployment. Just to be the devil's advocate on that, there were large-scale changes that accompanied the widespread use of pesticides and fertilizers too, so this is part of the ongoing manipulation of the environment that humans have indulged in for thousands of years.
On December 1st, 2009. See this statement in context.