There must be reason for the low mileages being reported, but I have been getting consistently 31 mpg highway (100% highway driving, 65 mph cruise control, with some terrain) and 26 combined. I'm guessing from that, that the city number must be about 21 based on my driving mix. This is not doing any kind of "fun" driving on my part, which probably would reduce the mileage drastically. This is approximately 4-5 mpg more than my 2005 330xi, driven the same way.
I also have observed that Eco-Pro saves only a few miles a tankful. For people with low highway values, have any of you tried resetting the mpg logger and then driving 20 or 30 miles of 100% 65 mph CC highway driving? I'm just curious what you get that way.