Final Fantasy XIII promises to be a damn big game, but according to art director Isamu Kamikokuryou, that's only a percentage of the sheer volume of content that was made. Apparently, there is enough deleted stuff to make a whole new game.
One of the cut locations is a park area that surrounded Lightning's home. There was also a secret base for rebel group Nora hidden in one of the game's shops. XIII's amusement park area, Nautilus Park, also once included a zoo, but that's been left on the cutting room floor. These areas were complete enough to be running on PS3 hardware, but were left out to keep the game balanced and reasonably sized.
With so much content, it smells to me like DLC is in the air. Don't be surprised if a downloadable zoo pops up in the future.