Let me preface the following by mentioning that my BA is in History. In the late 80's and early 90's, I read a shit ton of dry, historical writing.
We are now in 2013, and Gaming at the World is "dry, historical writing".
It's not bad at all. Actually, it's very informative. I just find that I can only stomach reading it using the Kindle app on my phone when I'm in the crapper, waiting for the bus or something else that is of a limited yet random time frame.
I tried reading it in bed on my iPad and it put me to sleep. Apparently getting that History BA in my 40's would have required much more discipline than it did 20 some odd years ago.
If you want an interesting history of RPGs that can actually be engaging to read, try Designers & Dragons (currently out of print - soon to be a multi-volume release from Evil Hat). If you want a textbook approach to many of the background events leading up to D&D, Playing at the World could very well be your cup of tea.