Iwata goes on to say that the Mii customization system is about as complicated as they want to make an interface right now. Further, they're not interested in competing with the virtual world services on the market right now. If they were to enter the markplace, they'd "focus on doing things that nobody else would do ... We'd be sure to make it something that nobody would call it a product similar to another company's offering." There have been persistent stories about companies developing an MMO for the DS, though. Perhaps the handheld's unique nature would allow them to go outside their comfort zone a bit more?
How sweet would a Massive game on the Wii be though, eh?