Well, let's see, of the top 20 products listed there, I own three (#3 Midnight, #5 the Tome of Horrors and #14 Scarred Lands Campaign Setting: Ghelspad) and have read through, at least in part, through three more (#6 the Manual of the Planes, #11 the Tomb of Abysthor and #12 the Monsternomicon Vol. 1).
I've also reviewed one of them, the Ghelspad Campaign Setting.
In light of the recent comments on a lack of reviewers, I'd like to pipe in that, since November, I've punched out my first seven reviews, and intend on churning throughout my collection of books in the months to come. So there's that.
I will mention, though, that when a book isn't fresh in my mind, finding any words for it becomes a bit harder. I'd at least like to think that, in part, reviews aren't quite so common because folk don't think to review a book soon after they finish reading it, and then when they think to, their memory, and perhaps even opinion on it, has dulled. Not necessarily likely, but it's a nice thought.
I'll also second my own distrust in reviewers; I see far too many 4's in my opinion, when I think that logic alone dictates most products should be of average quality. I find the only thing a fanboy does for me is to make me not interested in the product that they're trying to sell me on, as I put little trust in their standards being particularly discriminating.
In regards to better splitting the products and changing around the review system...
d20 is a really broad header. While I'm certain that Mutants and Masterminds and Spycraft are great products, they don't seem appropriately placed on the same list as books like Nyambe or the Book of Taverns.
On the other hand, splitting things up too much similarly creates a smaller pool of products to compare to one another. And some don't necessarily easily fit into any one category.
Just in regards to those books I've read and own, though...
Midnight: This certainly deserves to be on the list. In fact, I'd say this is possibly the best D&D book I've picked up, period. It's a rich, beautiful setting with a strong ambience to it that ties well into traditional fantasy archetypes while remaining a thing all its own. However, its magic system could really use some work. I'm not completely sure it should rank at 5's across the board, though if any book I own would, this would be it. It's place at number three doesn't seem too far off.
Tome of Horrors: This book is huge! Quantity may not be quality, but with the sheer number of beasties in here, there's bound to be something for everyone, and probably a lot of it. It's place seems about right; just because most of the monsters in it are up-dates from previous editions doesn't make it a bad thing. If it worked before, then why not now, right?
The Ghelspad hardcover: Definitely a good, solid buy. It's different enough to stand out, yet still has, in my opinion, the makings of a mainstream setting. Having been the child of the Open Gaming License, the setting is a better fit for third edition than any of the older settings retconned and retrofitted for third edition role-playing.
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