Risk mitigation groups would gain some credibility by publishing concrete probability estimates of "the world will be destroyed by X before 2020" (and similar for other years). As many of the risks are a rather short event (think nuclear war / asteroid strike / singularity), the world will be destroyed by a single cause and the respective probabilities can be summed. I would not be surprised if the total probability comes out well above 1. Has anybody ever compiled a list of separate estimates?

On a related note, how much of the SIAI is financed on credit? Any group which estimates high risks of disastrous events should be willing to pay higher interest rates than market average. (As the expected amount of repayments is reduced by the nontrivial probability of everyone dying before maturity of the contract).