Usagi Yojimbo DojoBoard

I am looking to get the "Art of Usagi" book and was wondering if there were any differences between the hardcover and softcover editions, such as extra content and whatnot.

The only difference, as far as I am aware, are the covers--one hard, one soft.

It's a great book. I bought it for my birthday this year with my Barnes and Noble gift cards. Beautiful art inside, a great addition to your Usagi collection.