What is the process required to transfer virtual console games from the Wii to the Wii U

You require the physical Wii and an SD card to move everything over. Note that this is a "move", not a "copy"; everything that gets put on the Wii U will be deleted from the Wii.

Important! You will need to have both the Wii U and Wii on hand to perform a system transfer.

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3. If I transfer my games from Wii to Wii U, can I keep the games on both hardware?

• Once the games are transferred from Wii to Wii U, the games are no longer usable on the Wii hardware.

4. I forgot to transfer my digital games before I traded in my hardware, can I get these games back?

• Once the console is traded, we have no way to retrieve the data.

5. What Data is Transferred During a Wii to Wii U System Transfer, and what data is not Transferred?

The following is transferred during the system transfer process between a Wii and Wii U:

• Wii Software Save Data
• WiiWare and Save Data
• Virtual Console titles and Save Data

Source: http://www.nintendo.com/consumer/systems/wiiu/en_na/system_transfer_faq.jsp