I always wondered about book reviews.
I completely disregard the comments strewn about the cover and inside pages of books. You know the sort, things like “spellbinding” and “”dazzling”, or "Edge-of-your-seat-excitement..." (This particular one was by San Francisco Chronicle inside a book jacket). Every book seems to have them, including the really bad ones. The more generic the comment, the less likely it seems that the commenter even read the book. To me these are just a standard marketing gimmick. You don't even have to read the book to throw out these catchy phrases and they tell you absolutely nothing about the book or its author.
But book reviews are different. They usually have to actually tell you something about the book, so presumably the reviewer actually read it. But you also have to consider the source of the review. Are they gaining from giving a positive review? Do they seem personally insulted by something about the book? Is the review actively part of the marketing strategy of the book, or is it an outside reviewer, reviewing it for their own reasons? Is it a "professional" reviewer, or ordinary Joe blow or Jane Brown?
And, most importantly, is the simple fact that taste is relative. One person’s “deplorable string of literary garbage” will be someone else’s “most exciting read of the genre I’ve had in a long time”.
The ideal book review for me:
Don't make me read the whole review just to find out if I want to read the review. I won't bother, unless I'm bored and have nothing else to do (and I usually do have something else I'd rather do).
Nothing is completely good or completely bad. Even a bad book has some good characteristics that make somebody want to read it; after all it did get published by someone who presumably read it before investing their company’s money into it. And even our favorite authors are not without some flaws. Reviews should include both the good and bad points from the reviewer’s opinion. A review that is only positive reads like a paid advertisement and one that is only negative reads like a personal grudge.
Okay, now entertain me. Give me your review, tell me about the book, expound its virtues, extol its horridness, and give me both the good and bad about it.