According to several job postings, it seems Blizzard is very, very busy working on several new games with the number of job listings going through the roof. According to various descriptions on its career page, we could identify the game genres for at least 3 of these “unannounced projects”. Included below are also the links to those jobs as well!

Mobile MMO RTS using Unity engine

First-person action game for PC and consoles

Massively multiplayer game (MMORPG) based on Diablo IP