In Chapter 4, The Rule of Law, Elgin Hushbeck discussed Proposition 8 in California regarding gay marriage. The issue in that chapter is not the validity of gay marriage as such, but rather the proper way of changing existing law. Should it be done by the courts or through normal legislative processes.
In an update for the new, expanded paperback edition, Elgin notes:
Update: In May 2009 the California Supreme Court issued a 6-1 ruling upholding Proposition 8. However, this did not end the issue. Advocates for same-sex marriage filed suit in federal court, and as a result, in January 2010 a trial began which put both the traditional definition of marriage and the people’s right to define democratically the society in which they live on trial.
In a rather clear case of trying to legislate from the bency, Judge Walker today ruled the proposition unconstitutional (source). Doubtless this will go to the Supreme Court.
Update: A new review today from Chris Clark mentions this very issue.