I'm going to buck the trend and say NCG over JD2 although JD2 will likely be quicker out of the gate.
The reason why is because while JD sells incredibly well, it's not played very often. Avg play time per person is about 6hrs. So with such low useage, why are people going to buy the same game again?
DDR also has this problem, the original sells better then 2,3,Disney. People are happy with one in a series, especially the Wii crowd as can be seen by countless sequel failures. UNLESS they change it significantly from the original.
With NCG using WM it's not the same experience, nor does it have any comparable competition on the market. It's not sports like WSR nor a party game like Wii Party, and no other mini-game fest uses WM giving it it's own place in the market. It should see the same boost in interest TW10 got (but not 11) when it added WM . Also, with soooo few games using WM I'm sure people will be happy to find one that does, that also caters to their tastes (IE: Not RS2)
Also CG's hasn't been overused like Deca Sports, Game Party and possibly Rabbids. It's been years since a true CG so people will be more eager to try it out. Although Mike_Intellivision is right about the lousy Mini-golf negatively affecting the brand but since that was a spin-off people may be more forgiving.
