I understand their reluctance to drop the Wii brand. Since it's the name of a console that put Nintendo back to the top. But the "U" thing doesn't have any excuse, it doesn't even imply a successor and more like an accessory. If they are going to keep it Wii, at least give it a "2". Not even a word play with "too", it needs to be very clear for the consumers that it is a successor and a simply 2 can solve most of their name problems.
Personally, I would drop "Wii" too. Wii's run did leave a certain bitter taste in the mouths of traditional core gamers and there is no guarantee that the casual public has a attachment to the "Wii" name like core gamers have to the "Nintendo" name. I do think Wii's success with the casual public had more to do with their marketing efforts and the concept of motion controls, something that was rare to see in homes even outside video game, than it's simple name.
Focusing solely on the needs of traditional core gamers is the fastest way to become another gamecube. The Wii was a global phenomenon, and in our microcosm on NeoGAF we seem to forget that sometimes we don't really matter.