Nintendo's confirmed in a feature spec sheet that Wii U's eShop will be available from day one when the hardware launches this holiday.
Reads the fact sheet: "The digital storefront for Wii U will be available at launch and offer a variety of content for people to download and enjoy. Consumers will also be able to purchase and download select games that are also available at retail stores."
As noted by NWR, Nintendo didn't launch the 3DS eShop until three months after the system's release.
Wii U launches this holiday season. Catch up on the Nintendo E3 presser here.