Today Nintendo of Europe announced an update for NES Remix that would allow for more than just the Wii U GamePad to be used as a control method. This new title update allows the Wii U Pro Controller, Wii Remote, or the Wii Classic Controller to be used with the game.
— Nintendo of Europe (@NintendoEurope) January 29, 2014
You’ll be prompted to update the title when you start it from the Wii U menu. It’s nice to see Nintendo continuing to support all methods of control for their games.