Yesterday I went out for a drive and broke 70mpg in my Insight. I had my MPGuino just a hair over 70 at a few points, though when I snapped a pic it was showing 69.74, which is an actual 70.64mpg taking into account my slightly larger tire size.
Today my wife sent me this after going out for a drive in her Fit.
After taking into account her oversized tires, that's 71.5mpg.
She doesn't share her fuel logs with me but I'm fairly certain she's beating my averages by a fair margin as well.