The Dragons on Dazzle Island book was announced way back in April, but it's September 6th release date is drawing near. Barnes and Noble is looking to 1up Amazon's offerings with a free poster with pre-order, though they don't include an image or hint on what exactly said poster will be of.
If you want to roll the dice on it being something cool, go grab it over here! Considering the book is pretty heavy on the original art, I wouldn't be surprised if it does turn out pretty neat.
Thanks to Victor for sending it.