Nintendo has just partnered with Unity to get their fully scalable engine on the WiiU. There are several interesting titles that have been made using the Unity Engine. And with this announcement it seems that it up to the developer whether they want to offer their titles on the WiiU. So this announcement is a good win for the eShop.
http://www.ign.com/articles/2012/09/19/nintendo-forms-wii-u-partnership-for-unity-engine
The Unity website with several games made for their engine featured.
http://unity3d.com/gallery/made-with-unity/game-list