The stated mileage will be based on a full tank of gas I assume just to keep things simple. ie. Chevy Volt can run 640 miles on 12 gallons of fuel=53.3 miles per gallon.

Individually you will determine the mileage you will receive based on your current driving habits. Take for example:
My wife averages 900 miles a month.

On each Sunday we visit my parents (70 miles), every other day my wife averages 24 miles, averaging 2-3 trips per day excluding the 70 mile trip. 24/2.5= average trip of 9.5 miles. Based on those averages while using A/C, heater, driving up hills, freeway driving, etc… let’s say she only gets *6 electric miles per trip (63%). We’re looking at 100 electric miles and 109 gas miles each week with the 70 mile trip to Grandma’s. Based on the average *30 MPG in regular 2-Mode, her Vue will consume 15.26 gallons of gasoline ($49) for the whole month or 58 MPG!

Right now she averages 17.6 MPG in our Charger R/T, using 51.4 Gallons of Fuel ($164) each month.

*6 electric miles could also be 8 if GM has already taken A/C, heater, hills, etc.. into account.

*30 MPG could easily be 35 MPG as most of the gas driving will be freeway.

$115 ($1,380 per year) isn’t worth the added Hybrid expense for us, but at least we’ll consume less fuel and have fun doing it in a non-ugly, quick little SUV we all can fit in. The Plug-In Vue should be a great appetizer to the Volt I'll trade my Cobalt in on for 2012.