Are you really using a game that was released in the time Wii was on the "Fad mode" and Ps3 was in the "get a second job mode"? I mean how much people had a PS3 in 2006? how much people had a Wii? what was the attach rate? and finally, is COD 3 an example or an exception to the rule?
You don't like me using the PS3 version? OK, the 360 version barely sold more than the Wii version, despite being on a system with an existing install base, that was the home of shooters for pretty much two generations (Xbox and 360), and that got the game a week earlier than the Wii/PS3 version.
And the existence of an exception disproves the claim. The claim was that only Nintendo games and cartoony games sell on Nintendo consoles. What CoD3 proves is that other titles can sell perfectly well on Nintendo systems. The sales of future CoD titles on Wii also prove the point, in that, even without advertising, without key features from the other versions, and with a stigma, plus the fact that the most important title in the franchise, which kicked off its huge sales, was two years late on the Wii, the Wii versions still managed a healthy number that invalidated the idea of dropping support for the system.
Oh, and regarding the comparison of "fad" vs "get a second job", here's the thing - first week sales of the game on PS3 in the US? 12.3k. This compares to an install base in that week of 139k. First week sales of the game on Wii in the US? 43.5k, for an install base of 463k. So the game had a tie ratio (not attach rate, that's number of games per console) of 8.85% on PS3, and of 9.4% on Wii.