http://www.physorg.com/news107785290.html
I have read many articles, including one on PhysOrg that question the long term viability of a corn based biofuel alternative. The main hurdle being the amount of fresh water required to support the initiative. I did read an interesting article that had a reputable scientist suggest that the best way to move forward would be not to change the current sources of oil, but to plant more trees to sequester the CO2 produced from fossil fuel combustion.