I moved from the midwest to San Francisco. In my experience:

  -> the culture here is more optimistic and open-minded; people are more willing to take risks and try hard things
  -> the weather is more moderate
  -> the scenery is more interesting and varied
  -> there are vastly more (good) job opportunities for software engineers.
  -> Bay Area/NYC software engineers get paid more than engineers elsewhere *on average*. But they are also much more skilled on average. If you're skilled enough to be hired in the bay area, then you probably will be paid less than what you could demand where your skill is rare.
  -> cost of living is totally unreasonable in the bay area, and the stats understate this because many people here have massive effective subsidies from rent control and fixed property taxes.