I have a C Max with 2500 miles on it and I bought it December 21, 2012. I live in southeastern Michigan where it is winter. Average mileage since new is 33.6 mpg. Being new kills mileage. Cold weather hurts mileage. Trip to work is 18 miles with max speed 55 mph. Mileage has improved over the last few hundred miles and my commute to work is 38.5 mpg and coming home is 42.3 mpg. It's uphill (166 feet higher elevation) but I don't think that's the culprit. Route is the same. Car sits out over night before going to work for 12 hours so it's cooled down. Coming home the car sits in the company garage which is enclosed for 9 hours. So, I think the cold weather has a greater effect on mileage. Cold weather (below 20 deg. F) will restrain electric mode more than I would think. The batteries like to be warmed up before engaging.
