I'm a pretty big Amazon fan, I've spent probably $15,000 on Amazon.com in the last few years, enough to get a cheesy form letter Christmas card from Jeff Bezos a couple years ago anyways.
It's pretty common practice over at Amazon to axe reviews which users mark as not being helpful because they're "not helpful" duh.
They are pretty secretive about their whole voting and ranking system it's a critical part of selling books and gaining consumer confidence, not in that people need to trust that their vote counts but if a product gets 4 out of 5 it's actually a good product.
It seems some people's reviews count more heavily than others; people who are "top reviewers" and people who have bought the book from Amazon seem to get a higher weighting than those who have not.
It's also claimed that 1 star reviews hold only a partial weight of the other reviews because they are more likely to be biased, off the cuff and of course, high reviews sell more books.
It's also speculated that some products even in the same class use different algorithms to generate their "average". I've seen products with just 4 reviews which don't average evenly (out by 0.5 stars) where as others with around 20 do, I've tried to pick it apart but can't.
Also the book has an Amazon.com Sales Rank of #1,364 in Books, that doesn't mean it's sold 1,364 copies that means it's selling VERY well to be the 1364th most popular book on a store with MILLIONS isn't bad. (even if it was written by
her) although to be fair we're in a literature slump and new book sales are a bit slow right now, for crying out loud Tori Spelling's book is in 15th
If you want to make a difference, buy the book and review it (also they know if you review it before you've had time to actually have it shipped) and make sure you actually write a decent well rounded review explaining your viewpoint, not just boo it.
If this all depresses you, you might be pleased to know that "The Case Against Barack Obama" is in 20th place and it's still on pre-order until Aug 4th!
To see the top books go here
http://www.amazon.com/gp/bestsellers/books/