You could go for a 2 year master's degree at a university ideally in SV, but if you have to choose between a mediocre school in SV and a top school on the East Coast I'd go for the top school. This will get your foot in the door.
Try to spend 1 or 2 years in Europe working for a big institution and also start a submitting code to big, shinny open source projects in the area that is of your interest. Then you can build a portfolio. Also be active here, on github and on SO, will help considerably from what I've seen.