I'd cut Nintendo a lot more slack with the wii if they would actually create products that were games and market them with the same precision and deftness to non-gamers that they do their non-games. Instead they sort of cede the idea that non-gamers who own a wii only want simple and stupid non-games. This might serve nintendo's interests, but it sure as heck doesn't serve mine.
But those new gamers will eventually want something more, like all the people who grew up on a NES did. Some moved to Sega/Sony/whatever. Wii Sports is a gateway drug to gaming. Nintendo needs to be ready for when they want something more or all they are doing is providing somebody else an audience later down the road.
There was a social pattern with Nintendo that got them to Wii.
NES- New gamers, family friendly, big success.
SNES- Succeeds, but those gamers are hitting teen years and looking for anything a bit uglier in its morals like any teenager does. Nintendo starts to respond with stuff like Killer Instinct, allowing blood in MK2, and the rather dark Super Metroid.
N64- Nintendo gets abandoned by 3rd parties, Sony even more successful at appealing to a pseudo-mature gamer. Nintendo still tries to attract them with crappy acclaim fighters and the success of Goldeneye/wrestling games.
Gamecube- Nintendo comes in after its first loss, goes hard after third parties and mature titles and gets some back onto their home console. Despite this, Gamecube gets an even kiddier image somehow, as the mentality that started with the Genesis days has just grown over time. No amount of Resident Evil made up for Mario existing somehow. The FPS/wrestling audience they had before is captured by Microsoft.
At some point during the Gamecube's death and the DS/Wii, I think Nintendo said "fuck 'em" to the gaming audience who wouldn't change their minds about 'kiddy'. Nintendo wasn't going to give Mario guns to reach these people. So, they went around this audience, looking for the new people. But if they don't create a bridging game by the end of this generation, and keep it going into next, the cycle will just repeat.