id Software is preparing to create something on next generation consoles – something with a user interface, which narrows it down to any software of any kind. Luckily, the UI Programmer job listing that reveals this information also states id is specifically working on "an unannounced game on future-generation consoles."
As superannuation (who spotted the listing) points out, the listing calls for "Familiarity with id Software games, characters, brands and universes," which suggests the new game may be part of one of id's existing franchises: Wolfenstein, Doom, Quake, Rage, or ... Commander Keen. Probably not that one.