We were actually looking at these online last night.
I like them. It's about time that someone designed a car from the ground up to actually be a police vehicle.  The rear doors are awesome, and the back seat setup is even more so.  Completely separate from the front area- hose out the back and pull a drain plug?  Outstanding.
For those complaining about the speed- trust me, when you're trying to catch up with someone in an anemic CV, you'll wish you had a little more grunt.  The diesel is also 40% more fuel efficient than current stuff, IIRC (I average somewhere between 8-11mpg with a Crown Vic).  I don't think these are much/any faster than the current V8 Chargers anyway.
Carbon fiber is strong, too- the last time we pushed a cruiser out (bumper-to-bumper on the push bumpers), we ended up bending the mounts...the CV fronts aren't as beefy as they look.
Check out 
this video.  They make a good point- fire departments get specially built vehicles...as does the military...hell, even the POST OFFICE gets their own special stuff.  Why don't we?
If you're not a cop, there's a lot of stuff you likely won't appreciate.  If you are, you'll see that this is indeed :awesome:.