NBCC board member and 2009 criticism finalist Stephen Burt answers that question:
Stephen Burt: Jeff, you asked what reviews can do…or what critics can do…
Jeffery Shott: Yes, what can a book review do for a book?
Stephen: What can a book review do for a book? [It can] cause others to pay attention to it. Cause others to be interested in it. Describe it accurately. Do justice to it. Indicate what, if anything, makes the book stand out, seem original or memorable, or, indeed, accurate, or [what makes it] sound good. Describe the book as a work of art rather than as simply a representation. Say, and I’m going to misquote the philosopher Arthur Danto here, what is in the book that is not reducible to its content. Cause others to talk about the book. Indicate what about the book is deeply flawed so that artists and readers with interests similar to the author of the book will do better next time. Engage in a public dialogue with the author herself about her new book and her prior books and, perhaps, her next book. Indicate, as in the case of James Wood and hysterical realism, what is, for good or for ill, and it often is for ill, typical or representative about a book, either of kinds of books, or of the age, or the culture that the book comes from. Differentiate the book from other books that seem similar. Indicate that the books has some kind of internal variety or is divided within itself in a way that other readers of the book, [if it] is widely reviewed, haven’t noticed. Bring, and this is my very favorite thing to try to do as a reviewer, bring to the attention of other readers a book, an author, or a work, that doesn’t seem to have been noticed at all, and that deserves attention.
Jeffery: (Pause) Yeah. (As in: what more can anyone say about that? Pause. Then strong applause).
This information was previously published here, and can be heard by listening to the podcast linked on that site.