BUT that might mean that Gamepad/Pro-controller support may be coming to Wii disc games in the future that use the Classic Controller.
EDIT: It's technically not identical to Wii discs... because Wii discs send you to the Wii home screen where you have to select the Disc Channel. SMG2 digital skips that step and boots you straight into the game. Hopefully that feature comes to Wii discs too.
yes, the same save data works with both disc and digital.