You make criticisms all the time. Don't be wishy-washy. When people read reviews, they can say that they do so for a variety of reasons, i.e. a review is like a preview, they get the inside scoop, they like to know what's worth their while. They may say it, but they don't mean it. And of course, no one will take you seriously unless you use the right words.
Adverbs are also very important because they can make worn-out adjectives seem new again.
Yet another way to get a blurb is to write ambiguous sentences that use strong adjectives so that anyone can easily quote you out of context. Nothing makes you look more foolish than ignoring the critical bandwagon of the day. This point will now be known as the Theory of Relevancy. Corollary 1 of the above states that you should center your taste in the area just outside the mainstream in order to maintain any credibility. Corollary 2 of the Theory of Relevancy says that you can gain respect and credibility by going resolutely against the critical bandwagon or terms of relevancy.