Apple actually uses lower case Is, not capital Is.
(If Microsoft were to buy Apple, you might see an operating system called "iWin"...or perhaps Microsoft would be saying that anyway.)
I agree that "Wii" stands out visually but "!!M" is more "out there", especially with pronounciation. It might work better once we find out what it is, but hopefully we won't have to be told how to pronounce every new thing of Nintendo's, especially since punctuation is apparently available in Nintendo's alphabet. "Like, this is the new Nintendo %@*$!" Unless we were a race of Q*berts, that has no meaning to me on its own.
I think WiiCulture could be like Touch Generations for the DS (and I think Europe's got something like Bit Generations for the GBA). It could include a set of games, like Wii Sports, that have "Wii" in the title itself and are simple to play and don't require top-of-the-line graphics or epic storylines. Non-gamers will want a "safe" set of games to choose from, instead of suddenly picking up Metroid Prime 3: Corruption thinking that they'll be able to play it but then get intimidated away from games again when they find out it's not quite as pick-up-and-play.