Well, I got my copy today as part of my Christmas haul, and I spent probably a good half hour just using it to tune my "new" TV's settings (I like to use animation and other colorful products as a base when setting a TV's color; contrast; and brightness settings). I haven't had much time to play the game (I only got everything hooked up about 1 1/2 hours ago, and only got the game 2 hours before that), but so far it's better than I expected (I only just completed the first Fort). So far only two things bug me (and one of them is probably my TV not being quite set yet): first, is it just me or does Mario clash with the background more than he should (as in, you can see aliasing on the characters)? It's like he and he alone is a re-used DS model, which doesn't look right. I get the feeling my TV's sharpness settings aren't quite right, but if that were so why does everyone else look fine?
The other quibble is that I despise how this game handles picking items up. I tried playing the game with both the Wiimote on its own and with the nunchuck combination, and I much prefer how comfortable the nunchuck combo feels. It took a little getting used to using Z to run and B to fling fireballs (for some bizarre reason, even though they're mapped to the same button normally, you can't use Z to fling fireballs), but the major problem came when I had to start figuring out how to pick objects up. Once again, even though Z should have the same function as B, you have to hold the trigger and then shake the controller to pick up objects. It just feels unresponsive and silly, but that's the only motion control issue I have.
One thing I wasn't expecting, though, was how good the music sounds on this new TV and its monster speakers. I was testing the speakers on Bit.Trip Core and Darkside Chronicles, and it sounded badass there and sounds just as fantastic here. It's odd because I've watched video clips of this game on my laptop and it just didn't sound all that good.