Square Enix recently revealed that Tetsuya Nomura is no longer helming Final Fantasy XV. Now he can work on getting Kingdom Hearts III out quickly.
"We're regularly meeting schedule deadlines." Nomura said in an interview with Weekly Famitsu. "Unfortunately, due to the engine, there are areas on the visual side where we're struggling."
Talking about the Kingdom Hearts III intro teaser that is included with Kingdom Hearts II.5 HD ReMIX, Nomura said, "When we showed the gameplay demo, we received the fan feedback and I felt a lot of anticipation was directed at Kingdom Hearts III. At present we can't really show more, but I wanted to send out some sort of message [to the fans]." Nomura also added, "I also wanted to show people that [Kingdom Hearts III] is going to start from a place they won't expect."
Nomura couldn't specify exactly how far along development Kingdom Hearts III is, but he did note: "I'm currently writing the scenario and selecting worlds. I'm also designing new outfits for Sora and Riku." That kind of gives you a general idea.
Kingdom Hearts II.5 HD ReMIX is scheduled for release on the PS3 in Japan on October 2nd, in North America on December 2, Australia on December 4, and in Europe on December 5. Kingdom Hearts III is scheduled for release on the PS4 and Xbox One at some indeterminate time after that.