The court will take up the case of whether the ban was constitutional and will also take up the question of the legality of the 18,000 same sex marriages already performed but they refused to suspend the ban:

Responding to pleas for legal clarity from those on both sides of the issue, the California Supreme Court said Wednesday that it would take up the case of whether a voter-approved ban on same-sex unions was constitutional.
The court, however, stopped short of suspending the ban, which California voters passed as Proposition 8 two weeks ago after an expensive and hard-fought campaign.
The proposition, which overturned a May decision of the California Supreme Court that legalized same-sex marriage, has been challenged by a number of cities and civil rights groups, which say it is a substantial revision of the state’s Constitution, and therefore requires legislative approval.

Given the actions of the gay protesters recently, I would hate to be these judges if they ruled in favor of the measure.