This PDF contains 49 pages: cover, credits, contents, explanation/promotion of CreatureDaily.com , 20 2-page monster spreads (40 pages), OGL, and 4 pages of ads.
That amounts to 20 new Pathfinder-compatible monsters bringing terrible and fascinating new powers to your game. Of particular interest to me were the many mid-to-high-level monsters which dwell outside the dungeon in various different terrains (although tundra and snowy environments get a lot of coverage): as your game matures, your players may tire of the tedious underground dungeon crawls, and as GM you should be able to provide them with outdoor adventure.
The text is composed well and complete, providing reasonable monster origins, motivations, and tactics, as well as the requisite crunch.
The illustrations are beautifully rendered and colorful, clearly the work of a top-notch artist. The virtual paper texture is charming, yet unobtrusive; and well in line with the high standard set by Paizo's beautiful Pathfinder books. The layout helpfully provides a 2-page spread for each monster.
The high-resolution "PDF.PDF" version contains a bug which causes problems for some readers wherein several images are broken. Fortunately, the "WEB.PDF" version doesn not suffer from this problem.
The pages have no page numbers, and the contents page lists no page numbers; this isn't much of a problem when reading the PDF in a viewer, but if you print it for table use, you must depend on the fact that the monsters are alphabetized to find anything. Also, the PDF contains no "bookmarks" to structure the content, so to find a specific monster you must either memorize the PDF's page numbers, or scroll through the document's 49 pages. These issues are easy to correct, but until that happens, I will dock 1 star for this.
There are also some easily-overlooked typos and/or spelling errors.
Setting aside these problems, I suspect the real purpose of this product is not to provide great content per se, but rather to sell subscriptions to CreatureDaily.com , a task for which it is well suited.
[4 of 5 Stars!]