One of the best games ever created.
The first thing the player will notice is the classic Zelda feel and realistic graphics (in GameCube standards of course). Although the developers could have done even better job in some aspects (like the textures of trees) this is still a really terrific looking game. And the look is even better, if you appreciate the artistic style of this game.
Game plays just like other 3D Zelda games before it, which means that it is fantastic. Probably the only bad thing in the gameplay is that there are only two buttons (Y and X) where to put Link´s items in use. The Wii version has more of these hot buttons. And when the player starts to play, he or she must remember, that this is a long game: it will take anywhere between 40-60 hours in his or her first play-through depending on how much side quests he or she takes.
There isn´t a single second of real voice acting in the game. This was a big disappointment and reading can become boring in some point of this long game. Sound effects work and are familiar from previous Zelda games, but at least the next Zelda game deserves a full orchestral treatment and no more midi-music.
Twilight Princess is not a difficult game, but challenge like Ninja Gaiden is not the point of a Zelda game. The thing is to be an adventurer in this big world of Hyrule and in this respect Twilight Princess succeeds extremely well.
In short: Twilight Princess is a perfect way to end the life cycle of GameCube and it is also one of the best games ever made. In my personal opinion this is the best game ever created alongside Mega Man 2 and Metroid Prime.
What are you waiting for? Go out there and play this game either on GameCube or Wii.