I bought my 2006 Civic Hybrid in early January and have put about 1000 miles on it to date over about 60% city (30- 40mph) and 40% rural highway (70+mph). I have averaged 44.6 MPG so far, but this would be higher without the highway mileage. After I learned how to use the IMA for optimal mileage, those 35-40 mph arterial streets really bump up the average. The CVT takes a little getting used to, but seems to be a good system. I actually like the dashboard arrangement-- the placement of the gauges makes sense to me. The seats are not the most comfortable, but my last car had cushy leather so it's probably just me. Headroom and legroom are no prob for me (I'm 6'3"). So far, fun car.
Auto stop at long red lights, great mileage, fewer pollutants, dashboard layout, telescoping steering wheel, plenty of power if you really stand on the CVT, exterior design. It's fun to watch the instant mileage to the point that it's distracting, so good thing it's close to the windshield!
Get rid of the roof antenna (no room for kayak!), would like pass-through trunk, better sound system (I suppose it's not that bad), cushier seats. More power in electric motor (a la Prius) especially from a stop and up hills- that seems to be where the worst mileage occurs.