hmmm, well, My general opinion, is that Marriage is considered a religious institution meant to be between a man and a woman, a ceremony of great importance that is integral to many religious belief systems, and that the most even handed thing to do for everyone, would be to remove ALL legal benefits for marriage, let it remain only a religious ceremony with no government benefits or recognition, then offer everyone regardless of the couples sex federally supported Civil unions with all of the same benefits marriage had.
(I'm also for offering these civil unions to polygamists, as long as they are consenting adults, I don't see the harm in more than two people wanting to be in a committed relationship to each other.)
That way the religious people have nothing to complain about (although some of the REAL hardliners will still complain) and the Gay rights advocates will have nothing to complain about (again, some of the REAL hardliners will still complain) and voila! equality under the law!
Usually the best compromise, is the one the hardliners on either side wont like.
Just my two cents.