In a nutshell, the lawsuit to invalidate Prop 8 wasn't about marriage for all, it was about striking down a Consitutional Amendment in the State of California which took away rights already granted to its citizens.
The decision (should the Supreme Court grant review) could be USED by other people to argue for rights in their states, but the issue being decided is a very narrow one, not meant to be Federally applied.
My gut tells me that the Supremes will refuse to review, thus beginning marriages in California again. My hope is they review so that others can use this case in their search for equality.