Though interested at the start, I had somewhat predicted the low sales of Wii U so I did not invest in it.
I have a PS3 first generation (so hardware compatible with PS2) which I use myself, and a Wii which I use for party games, and my 3 yo plays Cars on it

and my wife uses for the Wii Fit.
For the foreseeable future I am well set. When the PS3 bites the dust, I will perhaps look at the PS4 (assuming there is a way to run PS3 and PS2 titles, perhaps in emulation.)