A portion of a TVGB interview with Astushi Inaba, the game’s producer, and Shigenori Nishikawa, the game’s designer...

TVGB: So if this is a big success will you move on to a different title on the Wii or are you thinking about sequels?

AI: Platinum Games has several rights so we’ll be developing something new after this, but if there is a lot of interest in MadWorld then maybe we will make another one.

Full interview here