since the introduction of this crappy ulsd, I have been reading up on biodiesel myself, until I make the switch I've been adding 1 qt. of 2stroke oil to a tankfull of fuel, in my freightliner and my personal truck. my chevy sounded like a ford or dodge before doing this. worst I could find on biodiesel is during cold weather it will clog fuel filters. so if you keep a couple of extra filters around there should be no problems. the lubricant properties of the bio. are superior to the new fuel out there imho, below are a couple of links for some good reading and info on the subject.

http://www.biodiesel.org/
http://dieselplace.com/forum/forumdisplay.php?f=14