Read in
Autoweek that the new C-Class due in August will have the Bluetec CDI, and it will be available in the US. With a little searching on UK Google, I found this:
http://uk.cars.yahoo.com/car-reviews/car-and-driving/mercedes-c320-cdi-1002977.html
0-60 in 6.9
155mph top speed
27mpg city, 37mpg combined, 47mpg highway
Yours for a base of $32,000
Sounds good to me; one hell of a commuter.