Even though President Obama's new national CAFE standards will lean on the stricter California standards for support and there was broad agreement that a national standard of this type is the way to move forward, the devilish details could still cause a disagreement or two.

Problem One is that the new CAFE rules don't start affecting new cars until the 2012 model year. Problem Two is that the whole EPA waiver thing hasn't been decided. While California will back down once the 2012 models are here, that state has announced that it still wants to be able to regulate tailpipe greenhouse gas emissions between now and then. The New York Times' Jim Motavalli explains that California doesn't see its rules for the next few years being all that tough for automakers to comply with using existing technology. The battle lines are still drawn, but they're getting a bit scuffed up.

[Source: The New York Times | Image: Mel. B under C.C. 2.0)