The trick is going to be sales. If games sell well on the Wii U, developers and publishers will find a way to take the money. Just like Activision did with Cod on Wii.
How comparable will the games be between the Wii U and PS4? That is a good question, and so far we don't know the answer. As others have correctly pointed out, the difference in H/W between Wii U and PS4 is of the same order as the Wii vs PS3, *but*, does that translate into the same difference in game quality? Perhaps increasing graphics is a function of decreasing returns - maybe you'll need 10 times more H/W power to produce 3 times "better" graphics. The Wii's lack of shader support was a big drawback for its graphical ability - just look at how the 3DS, which is hardly more powerful than the Wii, can produce much better looking games. Will the PS4 have a similar killer feature that elevates it above the Wii U?
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