got it from Amazon last night, tried it out for probably an hour or so.  bit of background about myself: classically trained pianist, and pretty much a "casual" gamer.

it has completely surpassed my expectations--although it's kind of like the Sarah Palin VP debate since the bar was set so damn low. 

still, it's the most fun i've had playing a game since WarioWare Smooth Moves.  i underestimated how much fun it is to play a piece with whatever kind of variations you want on the theme.  the minimal amount of effort you need to make the music sound different is of huge interest to me. 

more on this playing variations on the fly: so far, i'm actually quite impressed that they've implemented all the algorithms to make the music come out correctly.  i thought it's really neat.  as somebody who knows both music theory and computer algorithms very well, i know it's not actually that hard to accomplish, although there are some careful decisions that you need to make in this process.  the IGN reviewer completely did not realize this--not surprising, since they don't appear to know much about music.  i don't know how the Mii Freestyle mode in GHIV is like so i can't make any comparisons.  also, it probably isn't new technology--but again, Nintendo manages to bring it to the masses in an easy and intuitive way, which is what really matters.

i find the handbell quite charming, perhaps due to its simplicity.  i can imagine it being a lot of fun playing with 4 people--the best part being that you need no musical background whatsoever to play fun.  but i don't understand why they only offer you 5 songs on this mode.  that seems absolutely ridiculous.

the wii maestro mode seems gimmicky, but it's also the one i enjoyed the most.  changing tempo to your whims is definitely very cool, and i think it's mainly fun because you'll actually (kind of) conducting.  again, just 5 songs? 

the perfect pitch game is too shallow, with basically only 5 kind of tests.  although if it were any more complicated, i don't know if i myself can play through the quizzes.  i think you can make an independent game out of this segment alone.

i haven't unlocked the music arrangement mode yet.  i'm very intersted in trying it out.  one reviewer mentioned that they have silly songs like twinkle twinkle little star, but what they don't realize is that the variations you expand on these themes are absolutely endless.  one of mozart's more famous variations is in fact variations on this twinkle twinkle little star theme:

http://www.youtube.com/watch?v=71f2fahFhDE

writing variations on a theme is one of my favorite musical activities--maybe largely because i'm rarely ever happy with any original melody i come up with myself.  so i just piggyback on a famous theme and expound on it.

rearranging music obviously takes a lot of effort, i'll have to try out and see how easy it is in wii music.  i've always wanted to write string or piano quartets, but the orchestration/arrangement is simply too much work for me.  it'll obviously still be a lot of work in wii music, since the interface doesn't take away the amount of thought you need to put in.

i'll get together with one of my violin playing friends for multiplayer and see what he has to say.  if we enjoy our "jam" sessions, then i'll go ahead say wii music is a success.

overall, i'm quite enthusiastic about this.  i'm definitely having more fun with Wii Music than either Wii Fit or Wii Play.  Wii Play is pathetic, but it's also only 10 bucks.

I don't know, I'm  also a classically trained pianist and a software engineer student and I was a bit underwhelmed by the game. I think their algorithm suck. It seems to be something like: if you're close to a note, play the note. Else, play a random note in the same key.

I know writing variations is cool even though I'm much more into original stuff myself, I was a bit disappointed that the result was just: it sounds a bit random.