Well lets try and look at this positively... as hard as it is.
High School Musical means singing which means microphone attachment. Which means... more crappy singing/voice/noise controlled games.
Yeah, lets just scrap the whole positive thing.
But seriously, this will be a very popular game whether you like it or not. Popular games mean more people buy Wiis. More developers see more Wiis being sold. More games get made be developers. More people buy games. More people buy Wiis. See where I'm going here, if people want their super-hardcore games, it'll take successful casual-aimed games to sell well before a developer tries anything ambitious.