Said to already be in development
It is hard to keep track of all of the buzz that we are hearing on the Wii2.
From back chatter we hear, developers Retro Studios in Texas (who have worked with Nintendo on a variety of titles like the Metroid Trilogy and the Donkey Kong Returns for Wii) apparently already have a Wii2 development kit and have been hard at work for some time on a showcase title for the Wii2. The showcase title for the Wii2 that they are said to be developing is a sequel for Donkey Kong Country Returns.
Sources tell us that the project has been in development for some time, but has only recently switched its focus to the new Wii2 from the original Wii.