@usgrovers: That is assuming every Wii U sell is a return customer that bought a Wii and Motion Plus remote. I even bought a launch Wii, but never purchased a Motion Plus remote. So, I had to buy a Motion Plus remote when I bought a Wii U. Also, I hear that a second Wii U gamepad is going to be pretty expensive when they are available.
Just too many moving parts to nail all of that down into a marketing message. What Nintendo needs is killer software and lots of it. In a couple months or so they may be struggling against the reality of new, more powerful systems.