This is a little bit of a personal crusade of mine - ethanol fuel, or E10, is not good for your vehicle and not good for the environment.  It’s also a dud from a personal finance perspective, in that it costs you more in the long run. Coverage (none of these are new):

• False Economy
• The Great Ethanol Scam

Why a personal crusade?  My car went through two fuel pumps in 11 months while I was running it on E10.  The particular model submerges the fuel pump in the tank, which accelerated the corrision that ethanol causes.