I thought that state of residency would be a big factor but from my experiences this past year, that did not seem to be the case at all. Even if you aren't a california resident, as long as you can sufficiently answer "why california?"/"why this program"? and you are competitive for the program, you will be sersiously considered. Of course if you have ties, like family/fiance/etcetc, that can only help your case.
Some programs post up lists of their residents and where they came from. Some programs do tend to keep their own or local folks but from what I saw, there were plenty that had residents coming from non-cali locations, like the midwest/eastcoast.