Confirmed, Non-Nintendo USB to Ethernet adapter working.
Nintendo.com forum member has reported:
“I just received a KINAMAX USB 2.0 to RJ45 Fast Ethernet 10/100 Base-T Network Adapter and it works fine with the Wii. Beats having to wait until January to have a fast reliable internet connection.”
“Does the wii channels and everything work fine?”
“Yes, so far everything is fine. Can send and receive messages, browse the Shop Channel, and WiiConnect24 is working.”