Prius vs. Civic Hybrid

Howdy. My Echo's getting on in the years, and I'm looking for a 4-door with excellent mileage in my price-range that is also environmentally friendly. My first and foremost preference would be for an all-electric, but since those aren't out yet, I did an EPA.gov search, and apparently the Toyota Prius and Honda Civic Hybrid are the best choices.

Toyota Prius 4-door Hatchback Sedan
Air Pollution Score: 8/10
Greenhouse Gas Score: 10/10
Mileage (C/H): 48/45
2008 - $21,416 (New Car Kelley Blue Book Value)
2007 - $20,945 (excellent condition, 30k miles)
2006 - $19,800 (excellent condition, 45k miles)
2005 - $17,980 (excellent condition, 60k miles)

Honda Civic 4-door Hybrid Sedan
Air Pollution Score: 9/10
Greenhouse Gas Score: 10/10
Mileage (C/H): 40/45
2008 - $22,654 (New Car Kelley Blue Book Value)
2007 - $20,365 (excellent condition, 30k miles)
2006 - $19,480 (excellent condition, 45k miles)
2005 - $15,920 (excellent condition, 60k miles)

After reviewing the KBB with equal mileage and years on both, it's obvious that the Prius maintains its value far better than the Civic Hybrid, which is another factor in which one to buy. The Civic, however, tends to rank higher than the Prius in the reviews, but the Prius has a more impressive list of mileage hacks (some that have claimed as much as 116mpg).

So... I think I may go with the Toyota Prius, assuming I buy a car before the all-electrics are out.

Anyone else have some thoughts on the matter?