There is now some more and eventually new (at least I havent seen this position yet) evidence on methane. From the Azimuth project page:
>The diff12 of methane values can be compared in an interactive diagram at our personal website
with the diff12 values of CO2 and Temperature anomalies from HADCRUT. The findings of Humlum et al. are recovered. Moreover it looks to me that methane diff12 values _precede_ temperature diff12 values (and thus diff12 CO2 values, which could be due to the decay of methane into CO2). Of course it is scientifically rather shaky to infer causal relations from such findings and thus it would be way too unsolid to infer from the above that methane might be a bigger driving force of global warming than CO2 - however it is suggestive to look for further evidence into that direction.
by the way it took me quite
an amount of time to do this interactive chart and Tim had to help me as well. I did this because I think it is an incredible important issue to look at and it seems somehow that things have been interpreted differently in the main stream.