Miyamoto gave his toughts about Wii Music, after 1 year he still thinks in this project.
"The development team members, the directors of Wii Music were I think, maybe a little bit shocked by the reaction and had hoped it wold get a better response than it did. So I think if we were to do anything, it would be a matter of getting back together with them and trying to understand what their expectations were and where the gap was between their expectations and what the resulting product was. (the) gap between the positives and the negatives seems to be pretty big. The thing that's interesting about Wii Music is there are people who are very versed in music and play the game and their evaluation of it is very high but at the same time there are a lot of people who play it and don't have a very good opinion of it. We have talked about it but it isn't anything that's concrete at this point."
Check the comments on Joystiq, they're priceless:
http://www.joystiq.com/2009/10/15/miyamoto-there-may-still-be-some-possibility-for-wii-music-fr/
In my opinion .... I don't know it's like a waste of time and effort, Mario Paint was a much better package in my opinion, Wii Music is something that feels incomplete for one reason or other.