This is an excellent way to deal with an issue. I’m not saying I agree with all the responses, but it is a very effective style to list each claim, and the response to each claim.
Now the responses are not conclusive. For example the response on how Kyoto will only lower temperatures 0.1 degree is pretty weak. Really it is just saying we have to start somewhere. Nowhere is there any analysis that the benefits outweigh the costs.
Likewise the article on China and India not playing their part is weak also. Firstly it is out of date as China is now a bigger emitter than the US. Secondly it only deals with an extreme case of should the US do nothing, because China and India have no targets. That is answering the wrong question. The right question is can one be successful at reducing overall emissions without China and India. The answer is probably no.
But the overall format is good. What would be good is to have another site that responds to some or all of the articles on the Grist site. Debate is good.