Quakecon 2021 is about to begin, and one of the things we already knew from a scheduling slip-up is that something called Quake revitalized would feature. Don't get too excited: it seems to be a remake with new content rather than a full reboot a la Doom. The now-deleted scheduling blurb mentioned Machine Games as the developer, and referenced "the additional content Machine Games have contributed to this revitalized edition."
Since this, additional hints have come out. The game's Steam page updated yesterday with a beta branch, which suggests that Quake Revitalized will arrive as a download for existing players. And now today an ESRB rating for the game has popped up, across PC and consoles. The description reads, in part: "This is a first-person shooter in which players assume the role of a soldier that travels through time to stop an evil force from destroying humanity[...] Some areas depict mutilated body parts on the ground or falling from ceilings." Sounds like Quake alright.
Unsurprisingly it's been rated M for Mature.
We'll almost certainly get the official announcement today: at 2pm EDT there's a 25th anniversary Quake livestream co-hosted by id Software and MachineGames. The full Quakecon schedule can be seen here.