With the current current glut of shale gas, there's a temptation to consider most of our energy problems solved if we can only move to gas from coal and imported petroleum products quickly enough.
Cornell's Robert Howarth has just published research indicating that shale gas is likely worse for climate change than coal over the next twenty years, and conventional natural gas may even be worse than coal. Over the next century, the differences seem to even out, but emissions from shale and conventional gas seem to remain in the general region of coal emissions.
Check out their Web site for more information. While I've watched less than a half so far, their video seems informative--or wait for their published paper.