This is entertaining, compelling, thought-provoking stuff. I can think of few other people who are so mindful of WORD USAGE, or in this case, I guess, WORD "USCAGE." Many insights in this book. I recommend it highly.
Perhaps the most interesting and rare aspect of the book is the pervasive inclusion of the environmental and more mundane details of the conversations. She is careful to note the frequent occasions when Cage laughed, what he might have been cooking that day, interactions with an artist who stopped by to fix a bookshelf as a favor to Cage and to Merce Cunningham. Especially valuable is the penultimate conversation, when we are made privy to the beginning of Cage's composition process, as he begins to write a new piece on the spot with cellist Michael Bach. These insights into Cage's daily domestic life are perhaps the most revealing aspects of the book into his personality and philosophies.
For those familiar with Cage, this is a must-read. If you are skeptical or confused about his work, these talks will clarify a lot for you. If you have yet to be exposed to Cage, I recommend this book highly as an accurate and exhaustive portrait.