"The truth about cars" blog has a piece about the 0.24 Merc today.
They're calling out M-B for touting the 0.24 number without making it abundantly clear that the only model that will have that value is the low-volume "efficiency" version.
Presumably also none of the photos so far released show that model.
See:
The Truth About The 2010 Mercedes E-Class Coupe’s Aerodynamics | The Truth About Cars