Nintendo has always been very focused on interface and design when it comes to the Wii. They have even scoffed at the need for their console to take the step to high definition, arguing that when a game is good enough, the level of graphics aren't as important. Recently, however, Nintendo demigod Shigeru Miyamoto indicated maybe an HD version is possible.
I don't think there's anything wrong with pretty graphics, and if I'm a consumer that has an HDTV, I'd want to be able to play my games with nice graphics too... And I think as we've seen the penetration rates for HDTV increase, we're going to see video games and Nintendo's games move along in step with the progression of technology.
What does that mean? Yes. When does that mean we'll see it? Who knows. Probably not anytime soon.