Basically - data shows that the stupider you are , the more is your belief in religion. And being intelligent means becoming an atheist ( with exceptions like me though - not very bright but an atheist anyway- so I produce only data no logic or opinion )
Gene Expression bloggers razib and godless were bored, so they plotted and graphed "religion important" vs. IQ for different countries. If you're in the mood, you can add the population data and have a real math fest. The bottom line: "religion and IQ are strongly negatively correlated (-.886)."