"Kingdom Hearts 3" is one of the greatest Moby Dicks in this generation of games. It could very well be the new "Duke Nukem Forever" now that "Duke Nukem Forever" is actually a thing. Even though interest in Square Enix's Disney crossover franchise has since waned slightly due to the glut of complementary titles put out in the name of the franchise, fans are still waiting with bated breath for this game.
Square Enix said nothing about "Kingdom Hearts 3" at yesterday's Tokyo Game Show, but instead showed a lot more of "Kingdom Hearts HD 2.8," because apparently it's really, really into the remastering and remaking business right now (just see the "Final Fantasy 7" remake). Now that we know "Kingdom Hearts HD 2.8" is coming out in January next year, it seems as though we won't be waiting too long for "Kingdom Hearts 3."
The Bitbag speculates that since "Kingdom Hearts HD 2.8" is intended by Square Enix to be an introduction to "Kingdom Hearts 3," then it's most likely that we'll finally be getting an announcement about the much-awaited third game in the franchise pretty soon. You can't really serve as an introduction to something if that something isn't about to come soon, so that line of thinking makes sense.
The only problem is that we might have to wait until next year's big E3 show and whatever Square Enix has planned for the event to even get a glimpse of "Kingdom Hearts 3." Keep your eyes out for a big event of the game's own, much like Square Enix did with "Final Fantasy 15," whose release date has been delayed for a bit. Even if we do get a release date for "Kingdom Hearts 3" however, it's likely that we shouldn't expect the game to finally drop until sometime around 2018, knowing how Square Enix likes to take time making their games.