The book contains cute little notes and helpful tips throughout, but no introductory material. It’s 21 lovely patterns bound together in a book.
I was surprised to see that all of the patterns in the book are available for individual purchase as pdf downloads. At around $5 a piece, if you’d like to make a few, then $20 for the book is a great deal!
Besides the discount over purchasing 21 individual patterns, though, you don’t get much additional content to the book. So, I would recommend having a peek at the included designs (which is tricky, since only the new 10 designs are listed as patterns in the book on Ravelry), and deciding whether there are a few you’d like to knit.
The patterns are cute and the book is very pretty… so if you can find a few, then I’d say go for it!