Ovenden has done something highly improbable: by collecting in one place transit maps for metros all over the world (possibly all of them, including some that haven't been implemented yet), he has produced a book which is so vastly entertaining I occasionally lost track of how much I was having to think as I paged through it.
Having ridden on some of these systems over the last 24 years or so, I got all the fun of trying to figure out which of the historic pictures/diagrams/maps was the best match for what I remembered carrying around as a tourist and/or staring at on station walls and in cars. Being a very amateurish design critic (I'm not a junkie, since so much of it repulses me), I got sucked in very quickly to the author's analysis of which kinds of maps worked well, and which other kinds of maps are tried repeatedly, even tho they have major problems. Partway through the book, I got kind of interested in what Tufte would say on the subject, and kept pestering R. for a summary, but R. didn't remember Tufte spending much time on transit diagrams/maps/pictures and got somewhat irritated at me poking at it. Neither one of us felt up to digging through the books upstairs so I resorted to google, where I quickly determined that, yes, once again, I think Tufte is largely useless. (The book includes some of Kick Designs alternate NYC diagrams, in case anyone is keeping score.)
Would anyone in their right mind carry this book on a trip with them? If someone did, I'd love to have coffee with them because I'm sure they are vastly entertaining. But that's not what this book is for. Part oooooh, cool, and I didn't know that! Part, holy crap that's a lot of tunnels. Part, wow those systems are growing fast. Part design history and criticism. Part what-is-transit-good-at. There may not be anything here for someone who can't stand leaving the woods or the desert, and has trouble convincing themselves to wear shoes, much less enter a city and ride public transit. But there's something here to amuse and enlighten just about everyone else.