It makes sense. I would expect the best architects to be in Chicago, the best finance folks in NYC, and the best media folks in LA -- why would tech be any diff

It makes sense. I would expect the best architects to be in Chicago, the best finance folks in NYC, and the best media folks in LA -- why would tech be any different? The Bay has a lot of extra draw for really talented developers. For the really good developers it's less about "what job can I get" and more about "what job do I want?". When they have the luxury to work at virtually any company they want, SV is the place to be just by the numbers. It makes a big difference to students too -- most hot shot developers out of college are going to take an offer from a flashy Bay Area sweetheart over the local healthcare IT shop any day.