Counterargument to Al Gore

I'm pretty much convinced that global warming is real, that it is exacerbated if not caused by human activity, and that the next 100 years will see significant climate changes. Although I'm generally skeptical of politicians, I think in this case Al Gore's facts are basically correct, that mainstream science is about as united as it can be, and that opposing the consensus is about as productive as arguing for a Flat Earth. Both Scientific American and The Economist have come out strongly approving the idea and, without time to do original research myself, until now I found no reason to question them.

That's why now I find myself shaken by a new 1-hr documentary from Britain's Channel 4 called The Great Global Warming Swindle. I watched it on Google Video, but I don't know if it was uploaded legally or not so it may be pulled by now. There is also a copy at http://www.jimclark.net (along with another bunch of content that, frankly, makes me skeptical of the facts in this video, but still).

The documentary quotes from many experts (former New Scientist editor, professors from M.I.T. and elsewhere, senior NASA scientists, etc.) who not only question the science behind Al Gore's movie, but offer convincing reasons why it appears that there is an overwhelming scientific consensus in spite of very good counter-evidence.

Briefly, the film argues that changes in solar activity influence earth's climate far more than anything we humans can do. Meanwhile, the way science is funded creates an industry of people who will be unemployed if man-made global warming isn't a problem. There is so much government money flowing to climatology study these days that, for example, a lonely scientist wanting to study squirrels will rewrite the application in a way to make it appear to be related to global warming. 

One interesting claim is that the whole concept of global warming was kick-started in the early 1980s when Margaret Thatcher funded research that would help discredit coal mining (and their unions) as a long-term source of energy.

At the very least, I am now wondering why we should let Al Gore's movie be shown to public school kids without also showing something like this one.  Anybody know if there are any counter-counter arguments?