The net result is, that this will cause a worldwide food shortage. Your car can drink a lot more vegetable oil/juice than you can, and guess what, there isn't enough agriculture in the world to switch to BIO fuels. There are still enough oil reserves for about 300+ more years at current demand (shale oil in Colorado), and coal for even longer. Ironically, they are making cattle feed out of petroleum ( synthetic protein, makes you wonder if this was the cause of MAD COW?) and burning vegetables in engines.
I think making engines run on California brush (instead of letting it burn in wildfires) would make more sense than wasting food resources on engines.
If the gov't were to tax WVO and E85 at the same rate as petroleum, no one would be using it in engines anymore.
I say it's less risky to drill out all the offshore oil around the US, than to start burning crops.