For example, both Sora and Riku will be playable characters in the upcoming game, and Nomura is promising some differences between the two characters. The reason why Sora and Riku appear as they do in the first Kingdom Hearts game hasn't been explained, with Nomura simply teasing that it is "a secret" and necessary for the story.
Perhaps the most exciting revelation from the interview is Nomura's intention to include brand new Disney worlds for the upcoming sequel. Although Traverse Town and "other original creations" will make a reappearance, it'll be interesting to see exactly what Disney worlds make it into the next game. Frankly, we're not even entirely sure what Square Enix has yet to dig up from the Disney vault.