Looking at the financial interests of the plays is definitely a good way to judge whether or not you need to be skeptical.
There is certainly a lot of money involved in avoiding global warming. Many new technologies are needed and a lot of new infrastructure.
However, the actual scientists who are studying global warming have no financial motive that I can see. They are not collecting the money from cap and trade or even from the new technologies. Their direct financial interest is actually in controversy. If global warming might be a big deal, more research is needed. This is great for the researchers. Actually saying that there is enough data to reach a sound conclusion could hurt the researchers. Now we can put the money into researching technology rather than climate. I don't think many of the scientist involved will collect much money from that.
On the other hand, you have players, such as oil and gas companies and the scientists from countries that are major producers of these resources who predominate the critical scientists. It is easy to see how these countries and companies would like to provide money to anyone who can cast doubt on the issue.
It must be quite a far sited policy (not something the US specializes in) to pay researchers to come up with conclusions that might allow them to raise taxes through a back door (cap and trade). It is either that, or companies (most of which don't exist yet), who are funding research into climate change, just so that the governments of various nations will all get together and end up in creating business for these companies. None of these options seems plausible to me. This is especially unlikely since the Bush administration was in power for most of the period when the current consensus was developed.
A more likely conclusion is: The same thing is happening with global warming as with smoking. You have lots of companies, countries, and individuals who benefit from burning fossil fuels. You also have a lot of people who enjoy the way that they live right now and do not want to be told that they are doing something that is bad (for themselves with smoking or for other people). It is easy to have those who stand to be hurt by any changes in the current system pore a lot of resources into fighting change.
PL/I -- "the fatal disease" -- belongs more to the problem set than to the solution set. -- Edsger W. Dijkstra, SIGPLAN Notices, Volume 17, Number 5