If you are really good at what you do, and if you understand how real startups work, it becomes clear that location is the most irrelevant factor to success. I second Jason's views. If someone isn't going to work with you because you refuse to move to South End, Mountain View, or Brooklyn, then they can go fuck themselves. I travel to these places quite a bit though, and I love having a career that brings me to both coasts often.

The Midwest is the perfect place for a startup. Now that being said, Chicago has an entertaining startup scene. Entertaining in that I feel like they are trying too hard to be like San Franscisco.