The last half of this book was a 5-star read for me. The first half, with the history of language especially, dragged so much I almost gave up on the book. I'd recommend to others to skip ahead a chapter or two if you feel bogged down -- the book isn't written in so cumulative of a style that you'll get lost if you skip some.
But once he got into information theory, Gleick really shone. I learned quite a bit from this book even though I've read a few books on the topic previously. And the style is very readable. I'm looking forward to reading other Gleick books -- I really like his writing style, even if I don't share his fascination with early dictionaries.