The difference about the colour green?

[Pino]

What is the difference between this book
it's not easy being green
an this book?
it's not easy being green

 

[KermieBaby47]

The second link shows a picture of the originally planned cover.

Before the book was released, they decided to go with the Kermit sketch cover instead of butchering Bert out of that great old photo.

 

[vertigo]

that photo was actually tweaked with quite sometime ago; it wasn't done for the book.