It did go out with a bang... it just didn't make it. Why does it matter, it's not like Wii Industries is its own company that threw GameCube Incorporated out of business. It's still Nintendo. They just created a revolution that was so great that it killed the GameCube. Pretty good, seeing them accomplish a sudden jump to a new system and be able to let go of the GameCube so quickly. Nostalgically speaking, this doesn't make the GameCube look too good though, but that's just the way things go. If the Wii hadn't killed the GameCube, Super Paper Mario would probably have been a GameCube game and not have sold as well as it has.
In short, the GameCube had a good run. That's why I kept my broken one. I want it fixed, eventually, for two reasons: for the nostalgic value, and starting GC games on the Wii is a bit of a hassle, not being able to navigate the menu with a GC controller. But let's stop mourning and enjoy the Wii.