The book is devided in three rough parts: Part 1, A TDD primer; Part 2, Applying TDD to specific technologies; Part 3, Building products with acceptance TDD.
Part 1, A TDD primer: This part is about Testing in general and covers refactoring and patterns as well. Everything is written with Test Driven Development in mind. So don't expect all possible refactorings and patterns covered here.
Part 2, Applying TDD to specific technologies: This part covers testing on specific technologies. Where the first part can help people start testing, the second part will help people continue testing even if the more complicated tests need to be written. Specially complex testing on Web components, data access, etc.
Part 3, Building products with acceptance TDD: The last part covers more on acceptance testing. I haven't got any experience with automated acceptance testing but this part covers it quite well.
Although this book has some influence from the Java world almost everything can be applied within other technology worlds as well, like .NET, Ruby and PHP. I like this book and will use it every once in a while to keep myself focused.