New Scientist - Crops 'widely contaminated' by genetically modified DNA
"Until now concern about GM contamination has focused on cross-pollination in the field. But the authors guess that much of the contamination has arisen from a failure to keep GM and traditional seeds apart during manufacture and distribution."

I am trying to keep an open mind about GM foods and don't dismiss them out of hand based upon the science and theory, but the troublesome thing about them, aside from the lack of adequate testing, is the fact that human beings are in charge of these things. Some slight human error in handling this stuff can cause havoc for a long time and for a LOT of people.