This essay discusses why the IPCC holds on to the myth and just waffles around the edges.
I would prefer at least honesty, but why would I expect it–these people have received millions to push warming/change/catastrophe. To admit to irresponsible exaggeration of the dangers of carbon dioxide increases in ranges much lower than historical levels in the past.
http://online.wsj.com/news/articles/SB10001424052702303725404579460973643962840#printMode