Well, maybe ...

... Three Golden Rules for book reviewing: What are they? - By Robert Pinsky - Slate Magazine. (Hat tip, Dave Lull.)

I've never thought of it that way myself. My own rule is that if you accurately and precisely record your experience of the book -- with appropriate references thereunto -- the reader will know how you feel about the book. Certainly reviews that focus exclusively or even principally on Pinsky's third rule are a waste.