Ethanol currently is the third largest consumer of corn produced in the United States and that is because of its great success and growth. Government subsidies given to ethanol and biofuel producton are four times greater than those given to domestic oil drilling, in the United States. The reason the government supports ethanol production so greatly is because it costs significantly less to produce than oil. In fact its predicted that by 2015 it will cost only 60 cents to produce a gallon of ethanol as compared to the current $3 it costs to create one gallon of oil today. This chart from the Natural Resource Report 2010 shows how much ethanol use has increased since 1995.
However, In order to feed this growth, more corn must be produced as well. If you're more interested in ethanol production and its success check out this report by the Department of Energy ---> http://tonto.eia.doe.gov/ftproot/features/biomass.pdf