Looking for a Visual Guide to Rails

I was listening to an older episode of the Ruby on Rails podcast hosted by Geoffrey Grosenbach and heard an interview with Amy Hoy. She was talking about an upcoming book she was writing for PragProg that would show rails from a visual learner's point of view. I became very interested in this subject since a picture is worth so many words and faster to process. After looking I have not found any trace of the book that was mentioned in the interview. Has anyone heard about this book or know of a resource that would provide this view of rails? Mostly, trying to get the picture on how rails interconnect and understand the magic better.

Thanks

Adam QED