Can we have a books.stackoverflow.com?
Something entirely w/in the extant structure--e.g., allow the Review to be posted as a question. Perhaps put a word limit.
Book Reviews are good, but you can find them on Amazon, O'Reilly, et al., so why should SO have them?
First, for reviews on SO, the reader knows something about the reviewer. Second, in SO, a book review is no longer a static text--the real value will be in the discussion it generates and the approval/disapproval of the rest of the SO community.
SO is a place for programming questions, so are Reviews really in the spirit of SO?
In addition, the SO FAQ tells us it's ok to answer your own question, which obviously means that providing useful information to the community is what matters, not the particular grammatical rubric in which the information is provided. So if it helps you, think of a book review (again, programming books, is what i had in mind) as asking and answering your own question.