Never-never land is a kind of utopia, a perfect imaginary place. If you're Peter Pan (or Michael Jackson), never-never land is a special place where childhood can last forever.
To a six year-old fan of cartoons and princesses, Disney World is a never-never land, and for someone who's incredibly hungry, an all-you-can-eat buffet might seem like never-never land. Any ideal situation or place can be described this way, although the original never-never land was the one in the original stage version of "Peter Pan," where kids don't grow up. In later versions of the story, the name was changed to "Neverland."