all 2010 5 speed models have a revised 5th gear ratio from previous years, resulting in lower rpms on the highway.
I have an 09 SE, on my recent roadtrip I was seeing as high as 38mpg highway at 70 mph. I was pretty surprised. I was very conscious of throttle input on the trip (no cruise control) and would draft other cars when possible.
Lately commuting I get around 33mpg.
I am starting to think based on all the mpg talk on here, the model doesnt make that much of a difference, just buy the accent you want, they all get nearly the same mileage when driven economically.