Four days ago, a job listing revealed that Bethesda is working on a "bleeding-edge AAA fremium game" that hasn't yet been announced to the public. Today, it's Blizzard's turn: As noted by NeoGAF, the studio has put up three separate job listings looking for an animator and engineers to work on a new, unannounced first-person project.
The descriptions for both Lead Software Engineer, Engine, and Lead Software Engineer, Tools are identical in the relevant bits, saying that Blizzard is seeking experienced engineers to work on a "robust first-person engine" that will power "an unannounced project." The ideal applicant, the listing says, will have "previous experience working on first-person or other action-oriented games."
The Senior Technical Artist, Animation listing, meanwhile, states that "experience with games that use a first-person perspective" is a plus.
Naturally, speculation on GAF is all over the map, ranging from the pragmatic (more Overwatch, possibly a single-player campaign) to the never-say-die (StarCraft: Ghost) to the unexpected but downright intriguing (a Warcraft RPG inspired by Witcher and Elder Scrolls). I'd be happy to play any of them, although it's the last one in particular that would have me throwing money at it like confetti at my best friend's wedding.
I've reached out to Blizzard for more information, but you probably shouldn't hold your breath while I wait for a response.