In their ruling, they state:
48 We have no occasion in this case to determine whether same-sex couples who were lawfully married in another jurisdiction prior to the adoption of Proposition 8, but whose marriages were not formally recognized in California prior to that date, are entitled to have their marriages recognized in California at this time. None of the petitioners before us in these cases falls within this category, and in the absence of briefing by a party or parties whose rights would be affected by such a determination, we conclude it would be inappropriate to address that issue in these proceedings.
http://www.americablog.com/2009/05/fascinating-footnote-48.html so if you were legally married in your state before Prop 8 passed and move to CA - are they going to recognize you as having a valid marriage or not?