While the focus is podcasting, this is the best marketing book I have read in a long time. I've always liked Tom's work and his voice, and that has not changed with listening to the audio version of this book. This is a really great product and resource.
The only reason it's not a 5-star for me is that it's not a book that everyone should read, but rather I would recommend it only as a must-read to anyone looking to build an audience. Tom knocks it out of the park in that area, so while no I wouldn't recommend it for example to my mother, I would recommend it to my friend working on getting a startup going, my buddy leading a marketing team, that prospect that is contemplating "thought leadership", and so on.
If you're at all involved in marketing and/or communications, read this book.