Barack Obama begins busting out the dread policy specifics, in particular a proposal to reduce the carbon content of gasoline. It's sort of like a carbon cap-and-trade scheme writ small, since it would apply only to the auto fuel market rather than the economy as a whole. This clearly isn't sufficiently ambitious to deal with the climate change problem and, to its credit, the campaign doesn't claim it is.
This is why, I think, people ought to calm down a bit about the demands for policy commitments. What to make of this proposal depends entirely on what else is or is not proposed along with it. As an idea, it's a good one. As a comprehensive approach to global warming, it's terrible. So one has to see if more good ideas come down the pike. This, by itself, is neither worth gushing over nor condemning.
UPDATE: Brian Beutler notes Barack Obama's January support for a coal-to-gas initiative that would be good for the coal industry in Southern Illinois, but bad, bad, bad for the climate. If he's decided to back away from that as he goes nationwide, that wouldn't be a bad thing. Certainly, it's something we all deserve clarity about.
UPDATE II: Okay, this doesn't as a campaign policy proposal per se, but Obama turns out to be one of the cosponsors of the comprehensive climate change plan formerly known as McCain-Lieberman. It's a cap-and-trade scheme with pretty good targets. Edwards' targets are better, but we'd have to consider ourselves lucky if we could pass Obama's.