Those worlds include Tangled, Hercules and Big Hero 6. All three of those worlds are likely to be quite popular and because the movies that go along with them were, the fans cannot wait to dig into them at full speed. The E23 Expo Japan is supposed to take place on November 6th and 7th.
At the Expo, Square Enix will showcase a new gameplay video for the fans and media, as well as possibly announce the scheduled release date for the game. The odds are very good that it will be in 2016, but depending on how the Final Fantasy XV release goes, they might be able to squeeze it in this year yet.
Other rumors for Kingdom Hearts 3 include Disney worlds like Frozen, Brave, Marvel, and Star Wars just to name a few more. None of those have been confirmed at this time, but were reportedly mentioned during a closed door meeting.