San Francisco is going to eventually collapse under its own weight. It's already extremely expensive to run a business there but if VC's get tighter with their purses going forward then it's going to be hard to start a new business there when your employee costs are so ridiculously high that you're burning at a 2x rate compared to your competitors in NYC, Boston, Chicago, Austin, Seattle etc (And yes I know some of those are closer than others to SF prices).