I bought this on a whim, because it's just a gorgeous book, chock full of old book covers. I figured I'd be interested in the contents too, of course, but was prepared, based on the title, for a lot of hyperbole.
Not so much really. I'd say the editors did a fantastic job of choosing books that most people would agree significantly affected, if not changed, the course of society. I enjoyed the narratives written for each one too; I learned at least a little something about each book, in spite of at least 95 of them being familiar to me already.
I knocked the rating back a little because some of the choices would have had a more localised influence than others (A Book of Mediterranean Food and The Cat in the Hat come most quickly to mind), and because there was a slight but noticeable political bias to the choices. Whether that bias was the editors' or history's, I don't know, and I can't argue the impact most of these books had, so it's a pretty small quibble really.
A nice book for the bibliophile or the armchair historian who enjoys the trend of history through objects.