Here's something I wanted to post as a comment to the discussion of reviewing that Aaron is continuing at his blog—but my comment was too long, dagnabit:

Hey Aaron—just wanted to say that I do agree with you about the value of a "cultural materialist matrix," aka history. What one ends up arguing with is the Ptolemaic effect of the reviewer's perspective becoming the central organizing principle of that matrix. I guess I'd like to see critics be a little more dialectical about their own stances. The polemical bent of most critics tends probably from the paranoia you speak of (something I am certainly not immune too)--and perhaps there's also a tradition in cultural criticism of fighting tooth and nail for "your side" and leaving the more judicious judgments and syntheses for those who come after you. I find myself wondering here, in my formalist way, if there might not be a useful distinction between the "review" and the "review essay." The latter would leave more room for pontification and tendentiousness (in the best possible senses of those pejoratives), while the former would commit itself to a more intimate encounter with the work itself. But obviously you can't be that neat--every book comes encased in a context or "scene." Once you start noticing the difference between a book by FSG and a small press book; once you know more about the "good" poetics of blurbist A versus the "bad" poetics of blurbist B, you can't ever go back. After such knowledge, what forgiveness, right? Gotta go now, but I'll keep thinking about this.