http://www.vg247.com/2013/01/24/wii...-gamepad-play-classic-pro-controller-support/
Here you can see what appears to be the option to connect two Wii U GamePad tablets to Virtual Console, which is odd as they arent sold separately yet. Perhaps this means they are on the way singularly?
This photo shows support for the Wii U Pro controller and suggests support from both the Wii classic controller (thats limited edition SNES version pictured), as well as WiiMote.