I have been thinking about the California Supreme Court ruling and its larger implications on society.
First of all, I see this as an issue that will soon be turned against the church, if it is allowed to stand.
1. If gay marriage is legal, and has the same legal rights as traditional marriage, then the church will soon be forced out of the orphanage and adoption business. The church will get sued by the first gay married couple it refuses to give a child to. It will likely lose that lawsuit. As a result, the church will have to get out of this business entirely.
2. Catholic schools will likely have to hire married gay teachers -- because it is only a matter of time before it gets sued for refusing to pay benefits to a gay teacher's partner. As a result, the Church will be forced out of the parochial school business.
3. No Catholic will be able to be a justice of the peace in California. Not that a Catholic justice of the peace can perform a sacramentally valid marriage anyway (if I were a Catholic JP in California, I would refer them to a Protestant JP and would not marry a couple, because as a JP I would have no standing with the church); but it is another area of the public square where a Catholic would have to recuse himself. I do not know if the simple solution of "I'm a JP but I do not perform marriages" will be tolerated for long; my guess is the first JP to refuse to marry a gay couple will be sued.
4. I really see no ban on polygamy or polyamory lasting long, if this stays in place. Honestly. I speak, of course, of non-Muslims and non-LDS offshoots, because it goes without saying that some traditional Muslims and breakaway Mormon groups practice polygamy secretly. I wonder who the last Muslim to be prosecuted for polygamy was (anywhere in America). At any rate, if marriage is a fundamental human right, and there is no procreative purpose to marriage (from the state's point of view), then I really don't see how the court can prohibit polygamy.