Environmental movements have for years promoted ethanol as an alternative fuel. The US and EU government slowly followed, introduced subsidies, for economical and environmental reasons (you choose). It is only in the last few years that came clear that only the financial argument stands. Each year we use the equivalent 400 years of plant growth in fossil fuels; we can't make up for that by just planting some corn. Production and transport of ethanol takes up so much energy that we might as well just use fossil fuels. The machine is rolling though, and is difficult to stop. I certainly hope the EU can set an example here, and put a break on it's subsidies. There are some arguments though that are greatly overlooked in the discussion.

• Brazil, and other Latin American countries, can count on technology and heavy investments from the US if they produce big amounts of ethanol. Ethanol is a temporary solution, which can not replace fossil fuel, but developing countries are changing the function of their fields from food production to fuel production for the US and the EU. Several countries are now protesting against the switch to biofuel (these are, "ironically", mostly fossil fuel producing countries like Venezuela).
• In the 20th century food production has been greatly industrialized. Most food we eat has been heavily processed, and species diversity has greatly diminished. Our diet started consisting largely of processed corn, soybeans, wheat and rice. The US has a giant overweight and obesity problem. How does the food industry respond? They take their heavily processed, non diverse products, and add "healthy" nutrients to them, depending on the current hype (currently being Omega 3).
  With the current switch to biofuel, I don't see this improving. A very interesting article about this appeared in the International Harold Tribune: http://www.iht.com/articles/2007/01/28/healthscien ce/web.0128foodMAGAZINE.php?page=1/.
• Let's also not forget the impact of this industrialization and lack of diversity on the quality of the soil: the monoculture and the massive use of pesticides, artificial fertilizers and irrigation water will become problematic, certainly for developing countries. Again, food prices will go up. And let's not forget what those pesticides and fertilizers are made of... Yup: fossil fuels.

The free market can be a good thing, but it has a problem: it works with a short term vision, it wants quick results. We will survive when biofuel doesn't suffice, we will find solutions, I am sure of that, but let's not forget about the footprint we leave, and the impact we have on less fortunate countries. It is not only the law of the strongest that should count.