Since Wii U failed, what should Nintendo have done to follow up the Wii's success?

[baloofarsan]

Soundwave said:

 I'd turn Wii Fit into its own channel with updating fitness challenges and lifestyle reccomendations. 

Anyone knows if this was a success for MS?

http://www.xbox.com/en-US/xbox-one/games/xbox-fitness

http://en.m.wikipedia.org/wiki/Xbox_Fitness