I'll put another shout out for F-Zero GX. I recently played it emulated on my PC at 1080p, wow! I then played it at 480p on my Wii and even then it's still one of the cleanest looking last gen games. Heaps of racers on screen, great texturing, blazing speed and a frame-rate that just wouldn't quit made, and still make, for an impressive package.
I'm looking forward to seeing what can be done on the Wii U.