I'm at a loss as to why people are talking about the Wii at all.
Publishers will freely admit to missing that boat. They didn't expect the novelty of motion control to take off like it did, and I doubt really even Nintendo expected such uptake. EA surely laments that they didn't think of things like Just Dance.
But, say it with me:
The Wii U is not the Wii.
The Wii U doesn't offer "novelty" in the way that the Wii-mote did. Regardless of how innovative and revolutionary and #gamechanging Nintendo's faithful fanbase think the controller is, the rest of the world that hasn't been living under a rock doesn't find the idea of a touchscreen on a console particularly groundbreaking. To the casual observer, pun not intended, it looks like a "me too" product against the growth markets of iOS and Android gaming.
Publishers aren't avoiding this boat because they're being overly cautious about a novelty, they're avoiding it because they don't see a compelling USP against other devices. If they ask themselves questions like:
- Who is the target market for the Wii U?
- Will they buy it and why will they buy it?
- Will it, consequently, expand the potential audience for a title sufficiently to justify the investment and opportunity cost?
And they come out with negative answers, then that's why you're not seeing Wii U SKUs.
In absence of the "hook" driving adoption, you're left with a system of comparable performance to systems already on the market at a lower price, with large established audiences and vast libraries of games to create value proposition. Even further to that, they have a vendor lock-in effect with regard to PSN and XBL accounts and friend lists and brand association with major third party franchises.
In absence of the "hook" you're left with a product that doesn't compare favorably to what's already on the market. I doubt any publishers are particularly regretful right now if they concluded as such and decided against green-lighting Wii U SKUs.