Biofuels (Jatropha) as alternative to Fossil Fuels

For those who did the question on nuclear being a promising alternative to fossil fuels, one of the arguments is that there are other alternatives besides nuclear. Few mention biofuels as one such alternative. Biofuels are from plants, usually food crops like soya bean, palm oil, sugar cane, corn, etc. But as mentioned in this article, jatropha is a special kind of biofuel in that it is not meant for food (hence will not drive up food prices when demand for its oil competes with the demand for it as food). It can also be grown on poor soil, hence will not compete for land meant for growing food crops. These are two major rebuttals for what are often major criticisms of biofuels as a substitute for fossil fuels. And of course, like all fossil fuels, jatropha is environmentally friendly in that it emits little CO2. As mentioned in the article, it has already been tested in vehicles and planes to replace petrol.
Qns:
1) 'Nuclear energy is the most promising alternative to fossil fuels.' Do you agree?
2) Does technology offer the best solutions to mankind's problems?