I dunno about 360 and PS3 making most money. Those games cost more money to produce, hype, and etc. Third parties could easily make a lot more from the higher Wii install base not to mention the lack of good AAA third party games. Of course whoever cashes in on the triple A 3rd party first will get it good, but the time to do it would be a couple months after MKWii.
It's similar to how Tales did so amazingly well on GC. The GC was dried up from RPGs and first good one comes, they go apes*** over it. On the other hand Tales of the Abyss barely sold better in Japan despite a larger install base and being a better game imo. A smart 3rd party dev would know that a good time to cash in and make a name for themselves would be soon.
Of course after a while with so many good games out good games will begin to suffer in sales...Okami for example.








