Digging your own grave again, Reggie?
Pricing, pricing. The Wii's momentum in terms of games is clearly dying after the last major launch - Skyward Sword. It's sales are far from dying currently as it's the holiday season, but look what happened to those figures before the holidays, it's spluttering dead. I don't really suppose that the Wii will continue lasting hand-in-hand as though Wii U becomes the real 3rd pillar for the company (like when Ninty wanted the Wii, GBA and the DS to go hand in hand). The future lineup's almost non-existent for the Wii, plus its Virtual Console's plain dead. Where's the momentum to keep the console in existence in the future, even?
Even if Nintendo insists that the Wii will be of a different league than the Wii U, most consumers will continue to view Wii U as the successor to the Wii. And I doubt that many will want to buy "outdated" machines like the Wii when the U's already on the market.
If Nintendo tries to pull a stupid trick off by introducing a steep pricing when Wii U comes out, I can guarantee that Nintendo's screwed big time. Even if consumers don't react as much, its investors probably would, after getting reminded of the 3DS.
What's more, the tablety controller seemed to seal the deal for Nintendo to actually do so.
It all comes down to pricing for the Wii U.
The Wii seems to be increasingly unviable to continue flourishing as it did back then (come on, 90+ million is actually rather market-saturating, just like the PS2 back then), and the Wii U will die if its pricing is deemed outrageous.