There is a lot of common sense in the above video. Shame on Digital Foundry (which is usually spot on) for jumping the gun and claiming they put the Wii U GPU performance in nutshell when over 30% of the GPU is still being examined and is unknown.
The working theory is that the Wii U GPU is able to use a mixture of Programmable Shaders with Fixed-Function Shaders simultaneously, thus making an extremely efficient GPU.
My guess would be that if developers who want to get the most "next gen" looking games would learn to use the Fixed-Function part of the GPU to achieve "DirectX 11" type effects along with the Programmable Shaders.
It's fun to speculate!