Story of the day: Mysterious Stacks Of Books In NYC! Well, they're not all that mysterious. I mean the article includes the name of the guy leaving the stacks of books around and some quotes from him about why he did it. So... Kind of the opposite of mysterious, really.
Anyway. My bookish heart finds this utterly delightful and is thrilled to know that there are such things in the world. My practical brain, however, can't help kind of agreeing with the people in the comments suggesting that leaving books sitting around outside is probably not the best thing in the world for them.