Size based CAFE standards for light-trucks?

The last time we heard anything on the NHTSA's overhaul of light-truck CAFE standards was in February. Automotive News now reports that NHTSA has decided to go with size based class system

Federal regulators soon will propose a fuel economy rule that divides light trucks into five classes by size rather than weight, industry sources say. Smaller trucks would have tougher fuel economy standards than larger ones, the sources say.
... Toyota officials were told the CAFE proposal will classify trucks according to a calculation that involves wheelbase and track width to determine the area bounded by a vehicle’s four wheels.

Remember that these changes will affect only the light-trucks (pickups, SUVs and minivans), and not cars. It will be some time late next month or early september when NHTSA will go public with the revisions. So, stay tuned.