I just went over to the dealership (about 6 miles) and got 70 MPG on the way over.
Everything was smooth and had minimal braking.
On the way back, the nuts came out of the woodwork. Horrible drive.
Got the inspection sticker on the car, but MPG dropped to 55 on the way back..
The big hill didn't help much either..
In regular east coast city driving conditions, I think you can do pretty well.
Just turn on ECO, don't jack rabbit and coast up to stopped traffic, lights etc.
Besides those two things, it's pretty much like regular driving,
but you get very good MPG..
I have not yet heard of anyone getting in 90-100 Mpg range..
The way the 'c' is set up, it might not even be possible to do during a normal commute.