When it comes to renaming the Wii U, my big question would be just what audience is Nintendo trying to get? If last year's E3 and their push for core-oriented 3rd party games is any indication, you'd think they were aiming for the core audience with the Wii U. But to the core audience, the Wii is not generally considered a favorable brand. If Nintendo's aiming for the casuals again, the Wii branding probably doesn't hurt the console (hey, if they didn't find the name "Wii" stupid, chances are good that "Wii U" doesn't bother them that much) and Nintendo probably has to stay with the branding.
It's all a question of what Nintendo wants to get from this console. Right now, they seem to want it both ways, and I don't think that split focus will serve either audience well if the Wii's lifespan is any indication.