Just got the Prius two weeks ago and couldn't be happier with the fuel mileage. Here I am on Cape Cod on vacation, driving all over the place and getting 63 mpg. Can't wait till it's broken in.
Welcome aboard! I actually got my best tank ever during my first two months of ownership. Haven't been able to repeat it since (54 mpg).
There are a few places where I continually got 70 or very near it, for long periods of time. We vacationed in Cape Cod a year ago, and that was one of those terrains and speed limit areas that allowed that to happen. The other is the 39 mile round trip to my dentist. I'd rather drive to Cape Cod again, even if it is more that 1,000 miles farther away.