In its recent decision in Lyrick Studios, Inc. v. Big Idea Productions, Inc., No. 03-10837 (Aug. 5, 2005), the 5th Circuit addressed the requirement in section 204(a) of the Copyright Act that copyright transfers be in writing. The general fact pattern is probably pretty common: the copyrighted matter was commercially successful, and the parties acted for a while like there was an agreement, but then the relationship soured and the original creator decided to do business with someone else. So the jilted business partner tries to cobble together a bunch of things that aren't agreements on their own, but, the argument goes, together -- voila! -- they constitute a "writing."
Well, no dice, said the 5th Circuit. The Court not only examined the documents in detail, but it also examined several other other cases involving disputes about whether a sufficient writing existed. So this case is one to keep in mind if you're facing this sort of question.
There's some other interesting stuff in the opinion about what happens to preliminary injunction bonds when the winner of the case keeps changing. (The copyright owner won a preliminary injunction, posted a bond, lost at trial, lost the bond, then won on appeal and wanted the money back.)