We don't have as much land as a lot of people think. Right now there are about 3.2 billion acres of arable land world wide not including arable land used as pasture (United Nations Food and Agriculture Organization numbers) and the world population is 6.5 billion. That means that currently the world population is existing on about 1/2 an acre per person for food and fiber (textiles). This situation is not likely to improve as the world population increases. The amount of arable land could be increased with substantial inputs (irrigating dry areas or deforestation for example) but will be challenging in the face of economic and environmental factors.
Large scale diversion of arable land to produce fuels on any meaningful scale will be impractical.
Before this latest price spike a bushel of corn was selling for less than it was in 1973. Hell, we all think we deserve a raise every 24 years or so, eh? It will probably be transitory due to the fact that almost every farmer in the area that I work (in the Nebraska corn belt) is planning to plant corn fence to fence on most of their farms and that will probably be the case all the way through the corn belt given the attractive price.