In an interview
with Miyamoto, he says the Wii hardware is basically the GameCube. Sure, there are some minor improvements in the video card and CPU but what you have is mostly the guts of the GameCube. I think that's part of the reason they can have a nice amout of consoles at launch as the controller's really the difference maker. Of course there are other improvements such as the Virtual Console and online aspect but that's all software. Nintendo has said before that there weren't much improvements on the system themselves so this isn't unexpected.
Now, how would people react if one of the big wigs at Microsoft or Sony said that their console was basically the Xbox or PlayStation 2? You know people would go ballistic and say all you did was create a new controller. Sometimes it is all about presentations and how well your fan base is.
Would you have spent $250 on an Xbox or PlayStation 2 with a Wii-remote type controller?