Tim Lambert is debating a Mr. Monckton this Friday - not clear whether the debate will be put online. I hope so, it would be interesting to watch. I think cutting edge research scientists haven't done well debating PR types who are willing to lie or deceive. Tim's climate expertise isn't cutting edge research, it's in refuting climate denialists and their garbage at his website. The question is whether he can translate the excellent work he does in blogs into the soundbites you need for a debate here.
Tim gets tons of advice in the comments at the link above and again here. I strongly disagree with the commenters who say Tim should carefully explain the science. Much more promising are suggestions to use an honest version of the Gish Gallop, something I called the Behar Canter. A reasonable alternative would be to take one or two attack points against Monckton and don't give up when he won't answer or lies (but be ready to move on if he makes some kind of maybe-it's-a-problem acknowledgment).
The only general argument I'd make is this one, "a take away theme in the debate. Mainstream scientists look at aggregate data to make their case. Skeptics use local and anecdotal data to sow doubt."
UPDATE: Couldn't get the live video to work. Hopefully it'll be available some time. Comments here suggest Tim went with the straight science approach. I think maybe even more important than the tactic is repetition. Monckton gets a lot of practice, so I hope Tim has repeat opportunities to get the same.