This is the news i founs on a Dutch page:
Kingdom Hearts III is in development. Tetsuya Nomrua reports That, the man behind the first two parts of Kingdom Hearts, in a guide on the Kingdom Hearts series.
"The release of Kingdom Hearts III depends on Final Fantasy XIII Versus, but the game is already in development," says the developer.
"There are two games outside of Kingdom Hearts III in a draft stage. I would one want to title this year alone. Next year, I would like to submit a game with several main characters. " If this Nomrua talking about is the third Kingdom Hearts, it is not known.
"The series are not ending in any case with Kingdom Hearts III. When Sora's story is over, it does not mean the beginning for a story of another character. Sora remains the hero [of Kingdom Hearts] to the end. "
source: (Dutch page)
http://www.nu.nl/games/2212592/kingdom-hearts-iii-in-ontwikkeling.html