Tabata is famous for having come in and steered what was then called Final Fantasy Versus XIII to safety after a tumultuous development cycle. It eventually morphed into the latest numbered entry into the longstanding series, which we thought was rather good. Prior to that, he worked on spin-off titles Final Fantasy Type-0, Crisis Core: Final Fantasy VII, and The 3rd Birthday.
The news release also states that the primary team that worked on Final Fantasy XV will form the core of the new studio – but they're also expanding, with numerous positions up for grabs on their new website.
No details have been given on what projects it might be working on at this time, although when Tabata spoke to Polygon last year he said he was interested in working on something entirely new. Given his efficient handling of Final Fantasy XV, we're cautiously optimistic that this could be a turning point for Square Enix which has become somewhat infamous for its dubious handling of projects in recent times.