Originally Posted by Catlady
Blurbs are endorsements. Reviews are intended to be critical evaluations of the work, according the reviewer's standards. A review is not an advertisement.
Would you equate an political editorial in your local newspaper with a TV ad from a political action committee?
Absolutely, especially these days. Most editorials are thinly disguised (or not even) propaganda.
Many authors have admitted to not reading the books they have blurbed. Many have said they've been pushed to do so. Some refused, some didn't.
Many reviews may not intend to be an advertisement, but they dissect the book in such as way as to extol its virtues or explain its failings. Much as an advertisement attempts to do.
In an ideal world an editorial would be an editorial. But for the most part they are an attempt to sway public opinion and extol or deride a particular candidate or ideal. Very seldom do they stick completely with facts and they use well-known techniques to "lead" the reader to specific conclusions.