My Prius is a 2006 and I think it's the bees knees. Aaron can quote you a lot of numbers from his sources that say some regular gas engine cars have the same mileage as the Prius, but my first hand experience is that I drive ~80 on the freeway, pass fairly aggressively, accelerate fairly aggressively as well, I commute 60 miles up and down a hill daily and I get about 40mpg, when driving for work and at the speed limit I hit about 53 highway. There is plenty of room for the three of us plus stuff, I fit totally comfortably, and it fits in SF area tiny parking spots!
I have had the tires replaced once, but other than that have had no maintenance in 3 years of hard driving. And I installed that electric only toggle, so I can kill the gas engine while driving under 30mph (until the battery needs a recharge or I am running the a/c).
My vote? If it is at all an option for you, I say Prius!