I am so glad to see this thread is still alive.
However, it all seems to come back to modeling, filtering/statistical manipulations of the data, and religious zeal.
I, for one, still believe in the theory of evolution rather than creationism, like the majority of scientists who study genetics and archaelogy. Is this an entrenched religious point of view?? Possibly. There is no evidence that creationists could present me, short of God itself revealed to me in all it's glory, that would change my "beliefs". So I am personally pessimistic that the beliefs of people who either believe in anthropogenic climate change, or not, will ever feel totally convinced. Sorry, Rog, but I don't think you will ever claim from, or pay, Dean on this issue.
However, I am definitely in the camp of people who still believe that humans, in the grossly excess populations this planet is now trying to support, are by far the biggest problem facing ourselves and other species of plant, animal, bacteria, fungi, etc...barring a strike by a very big extra-planetary object. As such, I feel a moral obligation (a uniquely human feeling) to mitigate as much of this human impact as possible. Like Nick, I think issues like birth control are more important than what car you drive (if you can afford a car and choose to drive it). But I also think we all need to tighten our belts, if only because we are rapidly running out of fossil fuels and "safe" places to dump our garbage. As mentioned more than once, I also think issues like fresh, clean drinking water are and will continue to be our biggest problems as a species.