The 20 poster you can see were specifically chosen for this book by Mike and Bryan. With most Avatar posters either competition or convention exclusives this will be a cheap way to get some quality Avatar posters at retail.
I will hopefully be able to pick this book up tomorrow, when I do get it I will definitely have a review/video up to better showcase this book, primiarily the quality of the posters.
In terms of the non comic store release date, Amazon will be shipping orders on August 25th.
Will you be picking this up?