It might just have been the best marketing move since Paul decided that you didn't have to be Jewish to become a Christian.
California's supreme court today made gay marriage in that state legal, not only for residents, like in Massachusetts, but for any Americans that want to go there and get married. Of course, a California marriage will not be recognized by most home states, but still, the appeal will be great for gay couples across the country.
When couples get married they invite everyone they know, gay and straight. The idea of having an excuse to go spend a weekend on the west coast is going to appeal to a lot of invitees. If you're going to travel to another state to attend a wedding, you're likely going to at least make a weekend out of it. You might take in some sights, buy some souvenirs, of course you're going to eat and shop. Many might even decide to stay.
This will likely be a big shot in the arm for California's tourism industry. In fact, when the matter of amending the constitution to overturn the court ruling comes to a vote, it may just be tourist related business that makes the difference in the vote.