Savage Worlds Deluxe, a hardcover version of the Savage Worlds core rules, is available as a PDF through DriveThruRPG.com. It's being pitched as a sort of special edition of the rules that expands upon, but doesn't invalidate, what came before. This version adds new setting-specific options, rules for social conflict, better and expanded examples, new artwork, and rules commentary from the creators.
I'm looking forward to the new book. I love the Explorers Edition's sleek digest format, which launched a Savage Worlds renaissance in my gaming group, but there are aspects of the rules (movement, rate of fire, vehicle chases) that I'd appreciate some elaboration on.
My only concern is how much of this content I already own from the Companions books. I hear that a not-insignificant-chunk of that content, like the species rules from the Fantasy Companion have been folded in. While it can be nice to have everything in one book, what I really want is new material to improve my game, rather than repackaged stuff that I already own (especially since some of the Companion material was already reprinted from the Fantasy Toolkit and the previous Savage Worlds hardcover.