As you can gather from the title of the book, this is a book about what IMHO is the world's best grape variety, Riesling. For a long time, it has been the favoured white wine variety of wine writers and wine nuts such as myself, probably because of three reasons: it has a lot of personality, it works well all along the scale from bone dry to intensely sweet, and it reflects "terroir" (local conditions) probably better than any other grape variety. It has been much less popular with consumers in general, but this has changed slightly in recent years, which is what the "Riesling Renaissance" is about. I suppose that the two main reasons are that German winemakers have been making a lot more of quality dry Rieslings and there is simply too much Chardonnay around.
Now, this nice book is rather about the Riesling producers and the Riesling-producing regions in general, than specifically about the Riesling Renaissance as a phonomenon. It is an encyclopaedic varietal book, not a textbook or a book with a story.
After a short general introduction, we get some text about each country/region and then a list of the main Riesling producers, together with some nice illustrations. After some details/statistics, there is a short text about each producer. In many cases, we get a few short tasting notes from the author's visit. While it gives some concrete illustration to the quality and style you can expect from each producer, these tasting notes will become outdated very quickly. I'm not sure if it's really a good idea to include them in a book like this.
Another objection is that the book is somewhat "thin" on the general introduction and the overview of each country, and that interesting pieces of information is spread here and there in the sections, although I doubt that anyone will read a book like this from cover to cover. For example, I think that the Riesling Renaissance as such could have been given more coverage. Despite these small drawbacks, this is a good book that belongs on every Riesling fan's bookshelf.