If M does not improve fuel efficiency in the next model, these numbers will keep going down. Having 14-20 mpg is ridiculously low for such an advance car in 21st century. I am one of those who would love to drive an M3 but walked away once I heard the fuel efficiency numbers. On top of it, additional gas guzzler tax does not help either.
I know many of you will be firing at me but turbo is the way to go for performance cars in the future. Although gas price settled for now (still much higher than it was a few years ago), it will keep going up as the demand increases (Chine and India are the main contributers to high demand). And more and more people are becoming more environmentally aware.