To be honest I would have to really really really take a close look if THQ made it. They do not scream quality games to me. I cant even really think of any of their games off the top of my head now that i think about it.
DarkSiders, Saints Row, UFC, Homefront, De Blob and Red Faction are their big names at the moment. They make good (But not AAA) games, but I'm not sure they could pull of the cross-over appeal type game Nintendo craft.
This all reeks of Just Dance mark II for me, a random Wii game coming out of no where and capturing massive sales off the Wii market. It appears innovative and original ideas can lead to huge payoff on the Wii, albeit it's still early days to get carried away. Here's hoping if it does make it big, THQ don't go overkill with games and kill the thing off a la Guitar Hero.