First, let me start with the most important point - this book is a well-researched, engagingly-written, very thorough history of the role-playing game industry (well, the first volume of it, anyway). That alone made reading it worth-while for me, and I enjoyed it very much. That said, it is worth noting that the title is a bit misleading, inasmuch as the company histories in the book proceed up to the modern day (or the end of the company's life, as applicable); the "'70 to '79" refers instead to the origin date of the companies detailed within. And that, dear friends, brings me to my first complaint.
The book is organized as a collection of articles detailing the histories of individual companies in the industry, rather than as a synthesized, holistic account of the industry in a given decade. This leads to some odd features. Some information about the state of the industry at a given time is repeated from article to article, as if the author expects the reader to approach each article separately. In other cases, though, only casual mention is made of information included in earlier articles, even if that information is highly relevant to the issue under discussion. In other words, it seems as if the author cannot quite decide if the book is meant to be read straight through or as a reference, a collection of articles to be consumed piecemeal.
This approach constitutes the biggest flaw in the history (thus far), and also explains the other major flaw in the work. That secondary but also very important flaw is that the "parallel narrative" approach makes it harder for the reader to integrate the stories of the various companies to create a singular picture of the industry in a given era. The author seems to show some awareness of this inasmuch as he reiterates certain points from narrative to narrative (which reinforces them in the reader's mind, but also constitutes very clumsy writing), and also in the inclusion of an appendix that summarizes, in list form, the major features of role-playing as a hobby in the era under discussion. However, he lacked either the motivation or the skill (or both) to take his initial collection of articles and forge them into a more coherent historical narrative. This is unfortunate, and I am not looking forward to (potentially) having to look back to the first volume to refresh my memory on some aspect of the industry in the '80's, '90's, or '00's when I read those volumes, as I cannot be sure the information will be repeated in the articles found in those later books.
This general problem of awkward organization is likely a function of the author's lack of training in historiography. This lack of professional training as a historian shows up in other minor ways, as well: the prose, while straightforward and engaging, is littered with inapt and outright incorrect usages that will grate on a reader of scholarly sensibilities (if nothing else, graduate training in history might have persuaded Appelcline not to use quite so many adverbs); and though the book includes a bibliography, the author does not provide notes to source various claims of fact, which means that even a discerning reader is forced to rely solely on the author to weigh the reliability of various claims. This is not to cast aspersions on the author's intentions, here - I think Appelcline is perceptive and well-meaning, and probably represents the veracity of various claims of fact honestly as he understands them. But it is a mark of the amateur nature of the history that there is no immediate way for the reader to access the source material to judge the facts for him or her self.
All in all, I enjoyed the book very much, and, in fairness to the author, it does not represent itself as a scholarly history. Still, I feel that an opportunity was missed, here. Appelcline put in an unprecedented amount of research on the history of the role-playing industry from the earliest days to the present, going beyond even the efforts of the magisterial "Playing at the World" (albeit with narrower focus). This set could have been the definitive history of the industry. Instead what we have is a very good account of the industry that is nonetheless flawed in important ways that make it vastly less useful (and arguably useless) as a secondary source for further work in the field, and all because of just a few key mistakes owing to Appelcline's lack of formal training in history. I would dearly love to see a third edition of the book, revised by Appelcline with the assistance of a professional historian, working from his original notes, that could serve as a viable secondary source, but I believe I will likely have to be satisfied with what we have already. As these things go, there are worse fates.