Pretty sure the dude that wrote that article from intel wasssmoking crack. He was then terminated for filing such a claim fcc regulations states that hdd are to except disruption interfere not transmit it. Thus the hdd would have problems not the wiiU
There is also another reference that macbook pro retina may be caused interference by usb 3.0 itself as well and they refer what intel said.
"It is critical that the receptacle connector shield be connected to a metal chassis or notebookenclosure through grounding tabs or screws. The receptacle connector should have a back-shield to ensure that the receptacle connector is fully enclosed. The USB 3.0 receptacle should also make good contact to the PCB ground by providing sufficient number of ground tabs to ensure a low impedance path to PCB ground. The USB 3.0 receptacle connector should have a robust mating interface to the shield of the USB 3.0 plug when it is inserted. Providing a grounding spring/tab on the top side of the receptacle connector, in addition to the grounding springs on the sides, is recommended."
In other words, if the connector looks cheap it probably is, and you can expect Wi-Fi and Bluetooth interference.
http://www.macobserver.com/tmo/article/usb-3.0-hard-drives-can-cause-wi-fi-interference