From the Kotaku article about UE4 not coming to WiiU
I figured I'd ask straight-out, so during the Q&A with Rein, I did. "Will UE4 run on the Wii U?"
"Hahaha no." Rein said, with expert comedic timing. The room erupted with laughter. As the laughs died down, Rein continued: "I mean, sorry, it's not really a correct answer. We're not… we have Unreal Engine 3 for the Wii U. Right? And Unreal Engine 3 is powering all kinds of amazing games, still lots of games are being made with Unreal Engine 3. We announced today about a new Unreal Engine 3 license. Unreal Engine 3 doesn't disappear because of Unreal Engine 4. But our goal for Unreal Engine 4 console-wise is next-gen consoles. That's really what our energies are focused on. If you want to make a Wii U game, we have Unreal Engine 3, and it's powering some of the best games on the Wii U already.
http://kotaku.com/the-wii-u-wont-be-getting-unreal-engine-4-462919060
It doesn't seem like they consider WiiU to be next gen.