I just bought a Wii U, and I've got a lot of Wii save data and VC/Wiiware games - enough so that it doesn't all fit in the Wii and I have to use an SD card to store many of my games.
From the instructions, it seems like all transferred data must begin on the Wii system, and any transfer overwrites the entire Wii U "Wii" memory, so you can't do a transfer twice. Is this correct? Do I have to pick only 512 MB of my saves and games to transfer and can't use the rest on the Wii U?