Here's another article on biodiesel:
http://www.autocar.co.uk/News/NewsAr...aspx?AR=233984 ... and it mentions that two manufacturer's have approved up to 30%, the HDi-engined Peugeot or Citroen. Not even Ford, who shares the Peugeot design in some of its diesels, will approve the B30 blend.
That's a huge nail in the coffin for me to consider a diesel vehicle. Since gas/electric hybrids emit less pollutants and get better mileage, they win on the "green" front. Diesel still has the most promise long term, but only when manufacturer's allow biodiesel.