I've been running E85 in my Saab for a year and a half. I've had the car for 2 years.
The car has 20k miles on it, and I've put about 15k miles on it with E85 mixes anywhere from E20 to E55. I averaged 32.5% ethanol over the entire time frame, and lately I've been running E40 exclusively.
So much for ethanol eating a hole in your gas tank, fuel lines, engine block, whatever.