Very interesting things are happening in the U.S. Senate:

http://www.climateark.org/shared/reader/welcome.aspx?linkid=43284

Senators have passed Senator Hagel's plan to develop and adopt climate-friendly technologies.

They've also passed a "sense of the Senate" resolution stating that climate change is a threat, requiring mandatory curbs on emissions.

Now they just need to choose between "cap and trade" proposals, which cap emissions and let costs vary; and carbon charges, which cap costs and let emissions vary around a lowered trend line.