These were among the first articles that went up and they needed updating. The articles can be viewed in the biodiesel FAQ located at 1000q: the FAQ index, see here: http://www.myturbodiesel.com/1000q.htm
One change I made:
There is a controversy about how green biodiesel is because of the carbon accounting. In some areas, forest may be cleared to make biodiesel producing crops and there is an inherent cost to producing, manufacturing, transporting, and consuming fuel. To dispel a major myth about the current controversy, biodiesel and other green fuels are not the leading factor in higher food costs. Food costs experienced a spike due to world economic factors, a rise in commodities trading, politically motivated subsidies and trade tariffs, with green fuels being a minor contributor. The major reason for the increase in food cost is the increase in price of crude oil, whose price increase is due to factors beyond the scope of this article.
While ethanol feedstock was never destined for human consumption, it does take away from acreage destined for human consumption and animal feedstock. The counterargument to this is that the same acreage or cleared forest may have been used for some other industrial use so it's wrong to say that the latest carbon accounting is the correct one. Because biofuels and their impact are so new, at this point it's best to do what you want because no single argument is conclusively the correct one. In addition, biofuel use should be adaptable. Ethanol production with sugarcane in Brazil is much more green than ethanol producion in the US with corn. Geothermal energy is a no-brainer in Iceland but it wouldn't work in Texas, where wind farms are becoming a major source of energy. Hydroelectric is great at a waterfall but a bad idea in Death Valley Desert. In any case, I am sure that biodiesel has a place in the future.
Since the article was originally written, oil prices have gotten to WTF levels. Attention on the real accounting of carbon behind green fuels has come up and criticism of biodiesel comes with criticism of ethanol fuel. People are blaming high food prices on ethanol, but the single largest cause in the increase in fuel prices, not the increase of ethanol production.
In the introduction to biodiesel making, I added some more links where people can learn more and changed some wording. Hopefully readers will find it informative.