This is pretty enlightening. I've asked same question myself many time "who are this people?" because tech population is actually very small percentage. From your answer it appears that that people living in these 1.5M houses are not all tech works but rather new double income families and old pre-boom residents.

BTW, Zillow uses 36% debt ratio which is like the absolute max that you can possibly get mortgage (i.e. worse case scenario). That kind of debt ratio only makes sense for incomes > $250K. Once you can take out $10K as your monthly expenses, rest you can pour in to mortgage. With that calculation $260K income + $500K downpayment would allow you to live in 1.5M house without cutting too many corners. The downpayment can come in from previous house ownership gains or from equity stakes. This is probably not a good idea because you are in essence investing in already overpriced assets. There is no doubt that pressure is going to continue and bubble can only blow up so much.