Entroper on 04 May 2007
You just have to look at the games Nintendo is targeting toward the more mainstream gamers: Mario Galaxy, Metroid Prime: Corruption, and SSB: Brawl. Then ask yourself, would high-resolution graphics make these games more popular? Personally, I don't think they would. Certainly gamers are more concerned with the art style in Mario and Brawl than the pixel count, and while Metroid Prime was one of the Gamecube's flagship titles as far as graphics, its appeal is that it's a Metroid game (i.e. exploration and puzzle solving), not a fast-paced graphical powerhouse like Halo or Gears of War.
