There's a lot of weird balances going on with prop 8.
The specifics of how "marriage" is handled IS considered a state's jurisdiction, hence part of the problem. THere is an actual federal law or policy (which are two different things, and I don't remember which it is) saying that states should recognize other states' marriage, so that straight people don't need to worry about whether or not they're still married if they move. DOMA (Defense of Marriage Act) signed by Bill Clinton made this untrue ONLY for gay marriages. There's all kinds of debate (I read it as: excuses) as to why he signed it and why he "had to" politically, but this is the number one NASTIEST piece of legislation currently on the books.
There's also some weirdness about courts versus votes of the poeple. The California history I don't remember as well, but there was something about people having voted on the ban before. It then got overturned as unconstitutional discrimination (which, historically, has kind of been the purpose of the Courts to preserve the rights of the minority). So, the people said "well if we can't discriminate according to our state constitution, let's CHANGE our constitution. Then we can make all sorts of crazy laws!". Which means the courts still don't know what to do with the couples who got married in the meantime (http://www.youtube.com/watch?v=8WpwA...next=1&index=4