Timothy Kincaid runs through different scenarios. Bmaz at Firedoglake analyzes:
[T]his California Supreme Court certification process is likely to take some time. Six months would be a miracle, a year is far more likely. First off, the California Supreme Court does not have to accept consideration, and there will be a briefing process on whether they even should do that. Assuming they then accept consideration on the merits, and I do think it extremely likely they will, there will then be a full briefing schedule on the merits before any decision.
... I still look for the California Supreme Court to certify this issue, and my best guess is they will find standing, the case will be sent back to the 9th Circuit for a merits decision and the 9th will uphold Vaughn Walker.
Lyle Denniston offers his thoughts. This I'd not heard before:
If it turns out in the end that no one has a legal right to be in federal court to defend Prop. 8?s constitutionality, it is unclear at least for now what would happen to U.S. District Judge Vaughn R. Walker’s decision in August striking down the ban under the federal Constitution. The two sides in the case disagree on whether that ruling would stand, unreviewed by a higher court, or whether it would have to be wiped off the judicial books. The Circuit Court mentioned that disagreement, but did not seek to solve it.
The best explanation for the 9th Circuit decision is not legal but political. If the 9th Circuit can dilly-dally just long enough, we may be able to moot the Prop 8 federal case with gay marriage in California before it gets to the US Supreme Court.