I prefer to tell you what you are going to find in it.
The entire book is built around the "Business Model Canvas". Smart, simple, savvy, sparkling, ... Why this has not been invented years ago? So you'll find everything on page 46: it describes the way a for-profit company works (should work?). In fact, the perspective is an outside one: the description is oriented toward the relation of the company (as a whole) with the outside world: its customers, its partners, its offers, ...
Once the Canvas has been introduced, you'll get familiar with it through a series of examples (p52) applying it to well-known businesses types (they are called Patterns: long-tail, free, unbundling, ...). Now, you are really familiar with the Canvas and its 9 building blocks and relationships.
Then, we are going to work with the Canvas to Design business models. This section is based on Design Thinking methods adapted to the Canvas (Ideation, Prototyping, Customer insights, ...). Really really exciting.
At this stage, you are proficient with the Canvas and ready to plunge it into the real world (Strategy section). This goes through some classical (SWOT) and innovative (Blue Ocean) techniques to improve and invent businesses.
To conclude, we are invited to follow the 5 steps for designing and creating a business model. This overall Process justifies (if needed!) the reading of the preceding chapters. You will take advantage of every bit you learnt previously to elicit, design and sustain/improve/change your business model.
Business Model Generation really is a must read business book. Ins't it?
P.S.: if you still need more before validating your order, you can browse through the book thanks to a 72 pages long excerpt. And after reading, you'll be able to grab other bits from the Business Model Generation site (including an iPad app!!!)