The cycle of the gamer that slacker describes also sounds eerily similar to Nintendo's fall from the top. N stuck to a formula, and when the audience "grew up" they stopped playing or graduated to PlayStation for more stimuli, rather than Nintendo evolving with them. Only this time Nintendo is starting over in an effort to change the demographic from the traditionally strong male demo to a flatter male/female split.
I can see Ian's concern, only my reasons are more recent. When Zelda/Rev comes out, it'll be almost 2 years since the last GameCube game came out that I wanted (Star Fox Assault.) In all that time, Mario Parties, infinite Mario sports games, Nintendogs, etc. get top billing while I sat back and watched. I guess you could call me one of those "dormant" players they're trying to attract with the Rev, but I was never dormant by choice. I always had cash in hand to buy the next Zelda, real Mario, Mario Kart, Star Fox, F-Zero, Wave Race, or a new deep IP they could come up with. Instead their goals for the second half of the system’s life were mostly cheap development/quick buck/Mario infinity titles that I can't get into. If Nintendo's strategy is remotely similar to their Cube strategy of the last 2 years, it's fair to me to say that there is room for some concerns as far as core gaming/hardcore/whatever goes. I'll simply end up becoming another one of the majority that "graduated" to another system for more stimuli. Heck, Nintendo's already given us license to do it.
Secondly, they've already discussed that the "hardcore" audience is only about 20%. Targeting the outside audience statistically shrinks that percentage. Those new players might become hardcores, but it's a process that doesn't happen quickly and there's no telling exactly what TYPE of hardcore they'll be... My Mom's a hardcore Pogo.com player, on there every night for hours (playing until the fully charged laptop battery dies) before going to bed. But I sure wouldn't want a console stuffed with Poppit, Fortune Bingo and Phlinx games any more than fishing or cooking games. If my types of games aren't there, then I won't play. "Don't worry they'll still make those games" doesn't squelch the concern because half of GameCube's life shows something different.