There is an excellent article about Ethanol in the December Panorama (PCA).
The Ethanol Big Problems:
Lower power and fuel economy out of each gallon ("rob Peter to pay Paul" syndrome), higher cost to produce it, the destructive nature of ethanol to older vehicles (even at just 10%), the cost of food goes up due to the demand for more corn, and the increase in corn crops is creating a bio nightmare with the increased use of fertilizer and pesticides.
On lighter note, can you imagine someday we're all griping about "Big Corn" instead of
Big Oil"?