I'm not sure what the general feeling is, but I was somewhat disappointed by Wii Music. For me, the best part of the game is being able to play drums using the Wii balance board. That's why when I first heard about We Rock: Drum King (think Guitar Hero for drummers) a few months back I was quite excited that this would be a pretty good game for wiiboard fans.
At the time there was no mention of the game having balance board support so I thought I would wait and see before mentioning it here. The game's publisher, 505 Games, recently released some PR for the game which is scheduled for European release this April and the bad news is that there's still no mention of balance board support which is a real shame. I've tried to contact 505 to confirm this but had no response so it looks like wiiboard fans will have nothing to look forward to.
It's not all bad news though. If you still feel you need to beat the hell out of a set of drums and don't want to buy Wii Music you could always download Wii Drum High, a free download that will let you connect your wiimote/nunchuck/balance board to your PC via bluetooth to control a full drum kit. Pretty cool!