UPDATE: Sorry, Deluxe Set is $349, not $399.
Anyone who purchases the $349 Wii U Deluxe Set becomes part of a two-year (November 18, 2012 through December 31, 2014) promotion that will give consumers money back for making digital purchases. For every 500 points earned through purchases, you get $5 back. Pick up New Super Mario Bros. U for $59.99, for example, and you’ll have earned 599 points, enough to get $5 back.
You will not be able to participate with a vanilla Wii U Basic Set, nor will you accrue points with purchases made on the 3DS eShop. The latter is bothersome, though one assumes (hopes?) Nintendo will come up with a way to unify the platforms, and allow Wii U Basic Set owners to purchase their way into the digital benefits program. Nintendo has not made any comments on this possibility yet, and the company confirmed the inability for Wii U Baset Set owners to opt-in when I asked today.
Weirdly, however, redemption points earned through Wii U eShop purchases can be used to buy games on the 3DS eShop. That's good but weird, I guess? A website is launching in December to help users manage their accounts.