There are quite a few reasons why choose Civic.
I don't want to discredit Prius, because that is also a good quality car.
Here are only a few reasons:

*As you mentoned it is based on a popular ICE body.
It is normal inside and out.
*The price. Civic comes standard with all the available options.
(Minus baseball caps and t-shirts)
There are no additional "Packages" to buy. It already comes loaded.
*This is the first "Normal" hybrid car that Honda has, and it seems that
they really took alot of time to make it very beautiful.
*No waiting list.
*If the electronic half should fail you can still drive the car.
*Dual trip meters
*I beleive HCH is a more "hands on, manual" car which gives me more control.
*5-speed transmission is available.
*Warranty:
Honda standard is 3yr/36K on the drive train (Including the main Assist components) and 75K on the battery.
Several extended warranties are available.
I bought the best extended warranty and it covers 7yr/100k bumper to bumper and 100K on the battery. (Or is it 150K? )

We have a few Civics listed that are getting very low MPG.
All these are on the first tankful, not really a fair comparison.
I got upper 30's on my first two tankfuls.
Personally I drive for max MPG and get 58-63MPG per trip, and 56MPG per tank.
For a more accurate comparison to "Normal" driving I can lock in cruise control and get about the EPA list.
However I won't get near the EPA est on the 30psi F/R tire pressure recommended by Honda.
Even at 7,500 miles I don't think my car is completely broke in yet.
The highest MPG numbers are all with the Honda IMA system.

There are other features with HCH which either isn't avaiable with other cars, or are available with additional cost. Some features other cars have aren't available on the HCH. (Like touch screen and rear wiper etc)

If you can test drive a Prius then please let us know how the two "measures up" in your case!

Steve

PS
Wh-oh yea!
Today the weather finally cleared into a bright 81 degree day with no wind.
beat my old daily commute record of 63.4 and just landed at 64.3MPG!
I think I'll arrange a link to the FCD photo later this eve...

Efficient drivers do it better.
1003 miles a tank personal record. 74MPG calculated. HCH1 CVT