I think 'Misc' groups together some quite distinct genres - I'd say Mario Party and Zumba Fitness are less alike than some games that belong to separate categories.
Going back to why the initial focus on 5m+ sellers, it was also partly because of the fraction of total software sold that these games account for. Now obviously Wii Sports (as an almost-ubiquitous bundle) accounts for a significant fraction of Wii software sold, but even with that, the data shows that whatever genre you want to say it belongs to accounts for a lower fraction of Wii software sold than FPSes on the 360 (and possibly PS3). In fact, CoD alone accounts for a comparably significant fraction of HD software.








