Their official FAQ has a lot of information on the game, including little tidbits like "what happened to your other game/partnership" (the answer is "both parties chose to move on", plus the Evolve contract expired back in 2016) and the fact that it's not Left 4 Dead 3, but a new IP due to "a whole lot of new stuff which makes it unique".
It feels like forever ago when Turtle Rock was on top.
While it is often counted as a Valve product - often mentioned in the same breath as Half-Life, Team Fortress, or Portal - Left 4 Dead originated with Turtle Rock when it was an independent development studio. After a couple of years of hibernation, the team behind Left 4 Dead is back and this time they're sticking to their guns with their latest game, Back 4 Blood.
Targeting the PlayStation 4 at the present, the release is being "designed from the ground-up as an original, premium title and marries the best of what made the co-op zombie shooter so successful with new features and state-of-the-art technology". None of that is too surprising, but it's comforting to know that Turtle Rock isn't straying too far from its roots. "This is a great opportunity to work with [Turtle Rock] to create a new gaming universe built specifically with the large co-op zombie shooter community in mind", said David Haddad, president of Warner Bros.
"It's hard to overstate what an awesome opportunity this is", said Turtle Rock's Chris Ashton. There will be a campaign, there will be PVP, but it will absolutely not be a battle royale game. But, the developer said it's not resting on its laurels. Its goal is to take all it's learned and push forward. It calls "Back 4 Blood" the "biggest challenge in this studio's history". No release date window has been announced, but the team is targeting PC, PS4, and Xbox One versions. "We love being able to announce, so we can start working with the community right away".