a gaming style nintendo could use could be a game where the controller isn't the wii-mote, GC, or classic. it would use the Ds as a controller, the game would come with a GBA-like cartridge that turns the DS' touchscreen into a small keyboard for typing, and you probably see where this is goin, an mmorpg that uses the DS for communications, and the DS headset which would aldo add for communication, and being the family friendly nintendo, the voice could only be used with friends. that an idea for a style of a game nintendo could use. just my idea don't hurt me.
edit: the ds cartridge could also work for other games nintendo could make as well as the internet channel or entering your name into areas.