Mercedes-Benz is definitely making strides to show the world diesel doesn’t have to be dirty. Their 2007 C320 Bluetec will arguably be the the cleanest burning diesel in the world. They will be using piezoelectric injectors for a more precise spray, a particulate filter to lessen the amount of soot that leaves the tailpipes, a DeNOx storage catalytic converter to severly cut down the NOx emissions, and a selective catalytic reduction (SCR) catalytic converter to further cut down remaining emissions. With 211hp and 398lb. ft. of torque it should be no slouch either.

Edmund’s Inside Line
Mercedes-Benz Alternative Fuels FAQ

And look here to see how diesel technology kicks hybrid’s butt in a 3200 mile endurance test.

Diesel Vs. Hybrid