Mario Kart 8 pushes Wii U to the limit?

[curl-6]

Of course it's not hitting its limit; it's too early in the system's life.

He even says in his comment: "I think it still has a lot of potential left, and I suspect there are more ways to make use of its capabilities that we haven’t even imagined."

By 2016 we'll have seen Wii U games that are a clear step above MK8 graphically.