True, but I don't think Math Overflow and SO are really equivalent: most of the Math Overflow participants are academics; if you asked the same question on a SO

True, but I don't think Math Overflow and SO are really equivalent: most of the Math Overflow participants are academics; if you asked the same question on a SO for academic computer scientists I think you'd get similar results, especially if you restricted the answers to universal truths, rather than things which may or may not be true at some point in time, or under some conditions. (i.e. Apache is a better web server than nginx is not a universal truth, and neither is OO is better than procedural, etc.)