On January 8, 2008, Scientific American published this article:
http://www.sciam.com/article.cfm?id=grass-makes-better-ethanol-than-corn
which describes the outcome of a study done on switchgrass culture by the Department of Energy. The results of the study were encouraging, demonstrating that switchgrass is capable of delivering as much as 540% of the energy required to grow, harvest and refine it into ethanol. This compares with about 25% for corn.