I am not sure if this was discussed elsewhere, but the EPA MPG figures are really ranges. City driving, the range is 51 to 69 MPG. Highway driving, the range is 43 to 59 MPG. Probably, this means that EPA expects 95 % of drivers to have a city MPG average somewhere between 51 and 69 MPG, and 43 adn 59 MPG highway. Another way to think of this is that 50% of drivers will have MPG figures BELOW the EPA numbers. And this is without taking into consideration the variation associated with real world conditions, that result in efficiency below that predicted by the standardized EPA numbers. Based on this, and looking at the numbers posted here and elsewhere, I think the Prius is doing pretty much what is to be expected.
