Although there were rumors since June last year, and it was clear that Rockstar is working on the next GTA, the official confirmation came in an update detailing GTA V and GTA Online for PS5 and Xbox Series X/S, which should launch on March 15th.
Unfortunately, Rockstar did not reveal any specific details regarding the next Grand Theft Auto, which will most likely be called GTA 6, other than the project is in active development and "well underway".
Rockstar said that it will share more information as soon as they are ready, so it could be a while before we see any new information. Take-Two might share more information during its Q3 2021 financial report that is due in a few days.
Earlier rumors suggested that the next Grand Theft Auto could be set back in Vice City, with a modern twist. Other rumors suggest smarter NPCs, content updates similar to other online titles, and more.
In any case, the new Grand Theft Auto is in development and if earlier rumors are correct, it could be launching in 2024-2025.