The trend speaks for itself. Predicted warming has not occurred and the actual temperatures are all more than one standard deviation below even the fixed 2000 CO2 levels (orange curve). All 6 annual temperatures lie below all scenario curves. The quoted error on a single measurement is 0.05 deg.C so we can now calculate the probability of these measurements being a statistical fluctuation.
year sigma probability
2006 1 0.32
2007 3 0.001
2008 4 0.0001
2009 2 0.04
2010 2 0.04
2011 6 <0.00001
The total probability that IPCC predictions are correct but the data points are just a fluctuation is vanishingly small ~ 10^-14 ! It is therefore possible to state with over 90% confidence that the IPCC 2007 model predictions are incorrect and exaggerate any warming.
I realize that using scientific studies to disprove hypotheses is foreign to many people, but as it turns out, such things have been useful before in the history of science. Further discussion of this result in context is here at Strata-sphere which takes in the current scene more comprehensively, and notes a disturbing trend: global warming supporters are increasingly telling bigger and bigger lies and heading into criminal fraud to support their hypothesis. This trend demonstrates that they are not doing science, but policy. And policy questions are open to discussion by everyone, perhaps especially by those not blinded by science.
I'm open to collect on those dinner bets, now.