My initial feeling was that this book would fill a market niche. There are many introductory books on Smalltalk but one that takes you beyond the usual material seemed to be missing.
With this expectation I found the book quite disappointing. Most of the chapters are not advanced at all. In an attempt to cover everything with the book most individual chapters tell so little and do not hit the point (e.g., patterns & frameworks) that they are next to being useless.
When the opportunity to become advanced is there (e.g., comparing "is-a" vs. "subclassing" vs. "subtyping") useful references are not mentioned and the subject is not explored sufficiently. In addition, quite a number of wrong information is contained. Occasionally, useful information is available but the most useful part is the accompanying CD-ROM.
Overall, disappointing. A different title (e.g., "The world of Smalltalk" alluding to the version comparisons and superficial discussion of many related topics) would probably create the right expectations. The book, however, consistently compares solutions and points out differences in four different Smalltalk products. This makes it attractive to someone trying to make a decision for a particular product.