Hideo Kojima has put the word out that his new studio, Kojima Productions LA, will be building the next Metal Gear Online and is looking for talented developers.
Kojima, speaking at the Eurogamer Expo as recorded by CVG, also revealed base building gameplay and smartphone support for MGS: Ground Zeroes.
It is uncertain if Metal Gear Online is planned as a standalone title or as part of the upcoming Ground Zeroes, but as Kojima announced his studio was hiring programmers, artists, and game developers "for the core foundation of a 3D action game", it seems heavily implied that this is its own game.
The original Metal Gear Online was released as a standalone title in Japan, but servers shut down in June this year.