From Michael Erard author of Babel No More: The Search for the World’s Most Extraordinary Language Learners, (Free Press, 2012) and Um…: Slips, Stumbles, and Verbal Blunders, and What They Mean (Pantheon, 2007).
I think the best review is a profile of the writer, a profile of the reader, a profile of the genre or tradition the book fits in (or aspires to be in), and certainly not a full profile, but a substantive gesture in that direction. A situatedness.
The question that it’s getting at is, can you have a relationship with this book? There are many ways to get at that question. A good review is written by someone who’s read the book more than once; a bad review, on the other hand, is simply a report of how you feel after having consumed something. You don’t have a relationship with a meal (though you may have a relationship with a cuisine, a chef, a particular ingredient, or a restaurant) — or with most meals, anyway.
I find that a lot of reviews — both pro and amateur — don’t know what it means to have a relationship with a text, or how to talk about people who also have relationships with texts. They’re purely lip-smacking, plate-pushing. Yeah, get the fries, but the burger wasn’t worth it. But the reader of that review needs to know more about that reviewer: how many burgers have you eaten before? How hungry did you come? What were you expecting? Have you eaten here before? etc.