On the AjaxRay site today there's a new review of an introductory book from Packt Publishing about unofficial wiki is a BIG try to help in this issue. Besides, recently Packt has published the first book on Kohana "Kohana 3.0 Beginner's Guide". Jason D. Straughan wrote this book for Kohana version 3.x.
The review includes an overall assessment of the book, a detailed description of how the chapters are laid out and some of the complaints he had about the book's contents - a lack of code examples in some places, demos/screenshots pointing out what the framework can really do and the inclusion of some deprecated methods.
Overall, the book is well organized, focused and will be helpful on it's purpose. I felt it's capable to teach Kohana to a new guy, in a smooth way. Yes, there have some printing mistakes, old (because they are changed in new version) function use and some other minor issues, but seems ignorable to me. I'd recommend it for Kohana beginners.