25%: review of early days of videogames. including a lengthy foreword by ralph baer where he greedily stakes out his portion of the 'inventor of videogames' title. this part is largely dismissable and you can get better info off of a few google searches
5%: talking about status of videogame as art, and trying to legitimize videogame theory as academic pursuit. also worthless
10%: basic technical talk about how games work. useful information, for the uninitiated
60%: good solid talk about games. including a crazy taxonomization of games based on space/time/narrative/genre, 4 separate analyses each of which errs on presenting *too* many categories, which i found to really stretch the mind even if some of them are a little implausable. it is original and interesting. tho this was written a few years ago, it still contains gems that haven't entered the mainstream dialogue, so well worth reading. also a nice essay on the psychology of archetypes in games.
it is interesting too because it is somewhat out of date. you can feel how different the world of gamethought is today than it was in 2001. they use a lot of examples of old games, which is good grounding for younger gamers. curious that the author uses the same examples over and over again (such as the Spy vs Spy game, which is repeatedly mentioned -- why this game?)