Ya thats what I heard - but I updated without even looking it up (risky I know!) and my first-run-of-Wii's-ever-made Wii and its WiiKey are working fine!
Got all of them - and the new one is just out too - Bit.Trip.Runner I think is the name?Bit.Trip.Beat/Core/Void are all worth checking out.
Each game makes use of a style of control really well.
Bit.Trip.Beat - tilting the controller up/down
Bit.Trip.Core- using the D-pad to control which side you want to pulse-on
Bit.Trip.Void- using the nunchuck to move the ball around the screen
Initially, the game play videos of Void had me a bit "meh, I don't get it" - but once you get playing it, it is really neat - it also has one of the better soundtracks of the series.
Core is probably one of the better multi-player ones. It's so easy to be off like a fraction of a second when playing alone and missing a dot - but toss in a second player, and you're more likely to hit what you need to hit.
Beat is pretty neat, but sometimes the accuracy of the control feels a bit 'off' - I wonder if the motion+ addition can help with this? meh.
All of the games are really hard though - haven't beat the 2nd level of either Beat or Void yet, and still cant beat Core.
So far, Void seems to be one of the weaker two-player ones - but is great single player. Moving two dots around the screen leaves one of the players feeling like they are not doing that much, and in the 1st level (boss excluded), there doesn't seem to be too many sections where having an extra person is that much use.
Worth dusting off your Wii for IMO - each game is only a few bucks