U.S. EPA has submitted a proposed finding to OMB that greenhouse gas emissions are pollutants that endanger the public's health and welfare, according to this report from the Washington Post. If finalized, it could lead to the regulation of carbon dioxide under the Clean Air Act.
[Update: EPA issued the proposed finding today, providing for a 60-day public comment period following publication in the Federal Register. A pre-publication copy can be found here. (Moved up).]
[Update: The proposed finding has now been published in the Federal Register here (as well as supporting documents). Comments are due on or before June 23, 2009, Docket No. EPA-HQ-OAR-2009-0171. (Moved up).]