Over 35% of the current batch is international (moved from outside of the US to participate in YC). Almost all of my startup friends from when I did YC came from outside of the Bay Area. One of the great things about YC (and why I'm a partner here) is that we run an open application process with no pre-requisites. You don't have to know anyone, come from some particular background, go to some specific school, or be from the Bay Area.