As I said in another thread, since it seems from the introduction to Chapter 1 that they plan on making further books of this type, I'm wondering if we'll have a series of "Volo's Guide to..." books, all with this sort of variant cover. You have to agree that four or five of this type of book altogether on a shelf would look pretty awesome...
Rumour has it that Ed is planning on coming out with mini volo's guides.