Nintendo Japan released another Nintendo Direct presentation with Satoru Iwata late last night, posted above, detailing the Wii U's storage capabilities and backwards compatibility with Wii games.
USB storage units and external hard drives up to 2 TB can be used with the Wii U, but must be formatted specifically for use with the system. According to the video, the memory of each system is slightly less than marked, as 4.2 GB of internal memory will be needed to store account and profile information. Additionally, the console must be formatted, leaving 3 GB and 25 GB of free memory for the 8 GB and 32 GB models respectively (scrub to 4:58 to see how the information breaks down).
The Wii U can play physical Wii games, Virtual Console and WiiWare titles, but none are compatible with the GamePad controller. A Wii U version of the Virtual Console with GamePad compatibility is in the planning stages, according to Iwata.
Additionally, Iwata announced that eShop points earned through the Deluxe Digital Promotion are usable in the 3DS, DSi and Wii eShops.
Polygon has reached out to Nintendo for more details on compatibility with Wii games, and whether these games can be played on the GamePad without the screen. We will update this story with more information as we have it.
The Wii U launches this Sunday, Nov. 18.