Just on the topic of the 3DS, I do believe the 3DS does give some insight on what Nintendo is doing/thinking ...
While you can get into an argument on just how powerful any system is, in real world performance the PSP produced results that were closer (and arguably worse) than what we saw for the Dreamcast. In contrast, the 3DS appears to be producing results that are similar to Gamecube/Wii games while rendering at a higher resolution and outputting graphics on 2 screens with one being in 3D; and Nintendo has recently made changes which unlocked additional processing power to developers for 3DS games. Certainly, the PSP was state of the art for when it was released and the 3DS (arguably) isn’t as advanced comparatively speaking, but the 3DS is clearly far more powerful than the PSP.
If you assume that the Wii U might have been designed with a similar approach, the jump from the HD consoles to the Wii U would be somewhere around the difference from the Dreamcast to the Wii; and, with Nintendo choosing to increase the performance of the 3DS after release as best as they could, it wouldn't surprise me if Nintendo tweaked the hardware for higher performance recently. As precident, consider than Nintendo increased the clockspeed of both the CPU and GPU of the Gamecube ( by over 25%) between its announcement as the dolphin at E3 and when it was introduced as the Gamecube at E3 the following year.







