Once they finish twisting this around to establish that it allows "marriage" for homosexuals, the next move will be to use it to revoke all concealed carry permits.
Think about it.
"A citizen or class of citizens may not be granted privileges or immunities not granted on the same terms to all citizens. Privileges or immunities granted by the Legislature may be altered or revoked."
Once they finish twisting this around to establish that it allows "marriage" for homosexuals, the next move will be to use it to revoke all concealed carry permits. Think about it.
I suppose it could go either way: Revoke all CCWs, or require that CCWs be issued to everyone on equal terms. Of course the reality is that the courts are not likely to be consistent, even if they should be. Indeed, I tend to doubt that the California Supreme Court will interpret the state Constitution as permitting gay marriages, even though it's a plausible construction. We'll just have to wait and see.
As far as marriage goes, it would clearly be within the authority of Article I Section 7(b) for the Legislature to abolish civil marriage altogether. That would be my own preference. That way marriage could again become a purely religious sacrament, and people could separately enter into civil contracts of their own choosing to replace the one-size-fits-all civil marriage contract dictated by the state.
If government-defined marriages went away, along with all the special privileges (and liabilities, in the case of taxes) associated with them, the gay marriage issue would cease to be an issue. Some churches and religions would only sanctify heterosexual marriages, while others would permit homosexual marriages. If people chose to identify themselves as "married" they could do so without it having any legal implications.