I just read on CreepyClassics.com that it's rumored that Universal will release 3 more Monster Legacy sets in the Fall. These are "The Invisible Man Legacy," "The Mummy Legacy," and "The Creature from the Black Lagoon Legacy."
These are not confirmed, but I believe sales of the batch that were just released exceeded expectations. I remember a few online stores including amazon.com, had them listed on back order before the release date "due to unexpected interest in these titles."
I hope that if this does happen, that they'll release them in a boxed set with three more of those awesome Sideshow busts.
Now, if they'll only release "The Black Cat," "The Raven," and "Tarantula" on DVD...