The Ninth Circuit U.S. Court of Appeals in San Francisco ruled 2-1 today, declaring Proposition 8's ban on same-sex marriage unconstitutional. Here's the money quote from Judge Stephen Reinhardt, writing for the majority:
Proposition 8 serves no purpose, and has no effect, other than to lessen the status and human dignity of gays and lesbians in California, and to officially reclassify their relationships and families as inferior to those of opposite-sex couples. ... The Constitution simply does not allow for laws of this sort.
The case is bound for the U.S. Supreme Court. In the meantime, the ban remains in effect.