Well the thing is, they're saying it's at least twice as powerful as the original gamecube, and one and a half times as powerful as the xbox. Now I understand wii is nowhere near the other two next gen systems in terms of power, that wasn't nintendo's intent. I also understand these are first gen games and those tend to be not as good as later releases as developers harness the power of the system.
That said, it seems like some of these wii releases were rushed and the graphics could have been done on a nintendo 64 as one of the reviews alluded to. Sure I'm not buying it for PS3 like capabilities, but I am still paying to get graphics that are better than the gamecube.
Compare Red Steel to Far Cry Vengeance, both from Ubisoft studios. For a first gen game, Red Steel looks damned good. The shimmering water effects and light source effects are simply stunning and look next gen quality. Then look at Far Cry, it looks like a nintendo 64 graphics.