Mario Kart 8 on Wii U is native 1080p and 60fps even with 2 player split screen.
The problem with Wii U isn't the games, its the system
* Missing useful Friend List that allows Invite / Join
* Missing useful Notification system for friends invite / message each other
* Missing system level party chat for when friends decide to group up and play something together
Oh and the Wii U OS is as slow as it gets. It still takes 20+ seconds to access Notifications and 7+ seconds to exit Notifications back to main menu.