Speaking to Gametrailers, in a chunk of footage you can see below, Epic Mickey 2 lead Warren Spector explained that the fully-voiced cast for the new platformer will regularly feature characters breaking into song, in that time-honored Disney fashion. These songs will apparently explain things and further the story.
Spector also told IGN: "This time around, in the second game, I just wanted to take a baby-step to making the full-blown interactive musical game. This is not it. Gamers, you tell ’em there are songs in the game and they start getting panicked, but I just want to see if people will accept songs in games and, if they do, next time I’m going crazy."