The US House passed an anti-climate change bill this week. It would be a gross exaggeration to call it a good bill. It's a silly patchwork of compromises and giveaways to special interests, and it's not likely to be very effective either. On the other hand, despite the hysteria being whipped up by the fringers, it's not likely to have significant adverse economic consequences anytime real soon either.
So what value, if any, does it have? It's a semi-symbolic start, which, if it proves useful, could be turned into something useful. Nonetheless, anything with so many moving parts is likely to pose potential problems, so the future needs to monitor it carefully.
Personally, I would have much preferred a more direct "carbon added" tax. Aside from greenhouse warming, there are lots of other good reasons for decreasing our carbon use (it's running low, it makes the country vulnerable foreign suppliers whose interests run contrary to ours, and it's subject to the notoriously wild fluctuations of fossil fuel prices.)
It's hard to pass any such plan for long range purposes, though. Humans were designed to be short range thinkers, so it's pretty hard to convince anyone of the dangers who isn't personally being roasted or drowned at the moment - and even those people are robably misguided, since short time period fluctuations dominate such events.