This is not likely to affect most of us, but Harper’s is now including a morals clause. This says that Harper’s has the right to cancel your publishing contract if “Author’s conduct evidences a lack of due regard for public conventions and morals, or if Author commits a crime or any other act that will tend to bring Author into serious contempt, and such behavior would materially damage the Work’s reputation or sales.” This is, IMO, over the line.
There’s a lovely article at the Book View Cafe (a lovely site for authors, btw). You can also read the original blog post by Richard Curtis on this topic here.