Well, the intention was not to be cavalier, but to try to ignore the risk side of the equation as much as possible, because thats what Trulia did, so the analysis could be comparable. Having read all the subsequent comments regarding risk, I now see that what I should have said is comparing renting to buying on a _cost only_ basis, w/o considering the differences in risk, is not a helpful analysis.

I still stand by the original assertion: buying in SF can be cheaper than renting (see the revised numbers), and the risk and reward there entailed is actually pretty small if: buying now (after a recent fall), getting a 30-yr fixed rate, and sticking around for ~5+ years