S. by JJ Abrams and Doug Dorst - worth a purchase?

[luvthemgiants]

i was sent this link by a friend when i asked them what they wanted for Christmas. I have purchased it for them, but now i am thinking that i might get one for myself as well.

http://www.amazon.com/S-J-Abrams/dp/0316201642

has anyone bought or read this? its such a strange format and original idea, could be either incredible or absolute dross.