I just came across this great post on author Jaclyn Dolamores's blog titled "Ten Types of Reviews That Make Authors Sad." Check it out, it's really good! I totally agree with all her points. And it got me thinking about how I approach reviews here on Reader's Dialogue.
When I read a book, I pay attention to things that I like or don't like about the book and make mental notes of them. When I finish the book, I review the notes I took and think - did the negative points get resolved by the end of the book? Did they appear only briefly, like once or twice? If so, I won't even mention them. Something that bothered me for one page is not worth giving a bad review for. And I know from reading experience that no matter how good a review is, if there's even one negative point, the enthusiasm for buying/getting the book is dampened.
Then I think about the positive points I took note of. These are usually much more extensive than the negative. (I guess it helps to read books in the genre I enjoy and by authors I know I like!) I pull out the three or four main points that pop up throughout the whole book and give each of these their own paragraph in the review to make them stand out.
I try to be specific - not to say only "I loved Stephanie!" but to explain what it was that I loved so much about her character. I think it helps readers decide which book to read if they know why someone thought it was good. I've come across the "Wrong Reader" problem (Jaclyn's Point #7) because of reviewers who simply say they liked the book, and when I get it I realize they obviously like elements that I can't stand.
I think blog readers get to know a blogger's likes and dislikes over time as they read more reviews, which helps when I love a book and can't quite put my finger on why - readers will trust that if I liked it, they will - if I've given enough detail about books in the past that they know my tastes match theirs.
Oh - and the Sloppy Slam (#1)? Whether it's a positive or negative review, as a blog reader what turns me off is vagueness or plain old bad grammar. Of course, I know it's not the author's fault if a blogger can't spell or use punctuation, etc., but I noticed that there's an irrational reaction to sloppy reviews that result in my not wanting the book as much as I might have. I feel like if I'm writing about an author's work, good or bad, I owe it to that author, as respect for her work, to clean up my writing and present it as clearly as possible.