Will The Supreme Court Decide CO2 Emissions Should Be Regulated?

Highly unlikely. U.S. laws governing air quality, including the Clean Air Act of 1990, are actually quite specific about not including carbon dioxide. To implement such a program, laws would have to be changed.

In any event, it has always seemed to me that greenhouse gas emissions can't easily be regulated. With other air pollution problems, if you regulate emissions, you regulate air quality, but with a cumulative problem like CO2, your efforts become increasingly ineffective with time, as concentrations inexorably build. There are better ways to address the problem (e.g., conservation and technological solutions) than through regulation.