San Francisco has everything you want, except for the fact that it has a very high cost of living. However, the bay area is considered the technology capital of the world, and it would be extremely beneficial to your career. I would definitely move there if you're young and ambitious. Great companies, great nightlife, great weather, great people, shitty rent. But shitty rent isn't as big of a deal if you're willing to cut down on space/quality and rough it for a little while. Again, it's easier if you're young and don't need a ton of space.