The antics of the upholders of the climate orthodoxy are becoming truly hilarious. In response to Nic Lewis's findings about the contradictions and failures of the draft IPCC report, we have now had no fewer than three "rebuttals" (Desmog, Media Matters, Think Progress) none of which link to the actual article. In fact none of them even mentions Lewis, preferring instead to concentrate on Matt Ridley's WSJ op-ed.
It does rather tell a story.
I think we can say that there is a consensus that the IPCC's models don't include their latest best estimates of aerosol forcings and that the empirical evidence suggests that that climate sensitivity is low.
There have been some scientific objections to Lewis's paper however and it's worth pointing these out.
BBD, commenting at Keith Kloor's blog, is querying the claim that the IPCC places little weight on LGM studies because of the huge uncertainties.
Lewis references this claim to AR4 WG1 Box 10.2, and I can't find anything like that in the referenced text.
And on Twitter, we have the observation that Aldrin et al also considered a scenario in which the cloud lifetime effect was considered and that this raised the sensitivity. The tweet says it raised it to 3.3, but this is the mean rather than the most-likely value, which is still around the 2 mark. The cloud lifetime effect is probably worthy of a blog post in its own right.
That said, these last two observations seem at least to be addressing Lewis's arguments and are worthy of follow-up.