3 stars for a general audience, 4 stars for an audience interested in the history of technology.
The book did a very good job of describing an almost magical place and time, and almost caused me to mourn the demise of the old monopolistic phone company, which certainly is a large part of the reason so much could happen when and where it did.
I didn't know much about this era, and was interested in the personalities that made the transistor a reality, and that started looking into information science years before anyone else even conceived of the necessity.
I appreciated how the book wove the personalities and the science of the discoveries with the business and the politics of the monopoly. I think the most interesting part was at the end, where Jon Gertner analyzed the conditions that supported such an environment, and speculated on how such a place could happen today, and the aspects that exist in modern companies.
Personally, I was hoping for more of the computer history, more insight into the development of Unix. The book never promised this, and so it's my own fault I was disappointed in this aspect.
However, even for the areas the book did cover, it never brought all this to life. The events never popped off the page or lead me into new ways of thinking.
I'd recommend The Idea Factory to anyone that is curious about the history of technology, but it isn't the book I'd suggest to stoke that interest in someone.