Questions on California Proposition 8?

Sure amendments to state constitutions can be revoked, the easiest way is to get the Supreme Court to rule that the state constitution violates the U.S. Constitution. Then congress (if the s wanted to try to ban gay marriage) would have to try to get a U.S. Constitutional amendment ped which actually requires 3/4 of the states to agree on it. Getting 3/4 of the states to agree on anything is dang near impossible.