I am interested to see what the Supreme Court does with the California Prop 8 marriage case. The facts in that case are such that the Court could possibly limit its ruling to just CA (or similarly situated states, although I don't know there are any). I don't think they will, especially bc there are a couple other cases with that one, if I recall correctly (and I am too lazy right now to go look it up). But the situation in CA with Prop 8 & marriage is definitely unusual.
Normally, most other states that have prohibited gay marriage have two groups: heterosexuals who can marry their partners & homosexuals who can't. The argument (a weak one, if you ask me, but whatev) is that no one is being treated any differently: no one, be it heterosexuals or homosexuals, can marry someone of the same sex; everyone, be it heterosexuals or homosexuals, can marry someone of the opposite sex. Thus everyone is treated the same under the law.
But in California, the situation is quite different. There is not such a neat, clean line drawn. Prop 8 means that no one FROM THAT POINT ON can marry a person of the same sex. But, there are already same sex couples that got married when gay marriage was legal but before Prop 8 passed. Those marriages are still valid even after the passage of Prop 8. So, no longer is there a sure division of no one can marry a person of the same sex. Because they COULD at one time & there are many legally married same sex couples in California. So, the analysis is different: the analysis should look @ same sex couples who could marry during the time it was legal against same sex couples who can't after Prop 8.
It's a really interesting question. At least for me bc I am a nerd. But it will be interesting to see what the court decides to do with it.