One of the things I noticed is that HG recently amended their complaint and are now claiming actual copying as opposed to derivative works. It seems to me that's a much taller mountain to climb.... am I out to lunch on that?
Let me hit that on the weekend, because I want to go a bit in-depth on those and the standards of proof required.
(Also, as for court documents with a sense of humor, this opinion in the Prenda Law case is still the best one I've seen. PDF link to Popehat.)