This walkthrough has been beautifully put together, masterfully presented with artwork of creatures and locations, really contributing to the feel of the game.
On the plus side it's always good to have a book besides you to learn what monsters are weak against, how much energy they have, and the game has helped with finding out the odd secret.
However, whilst Futurepress have tried their hardest to tell a walkthrough as simple and as tranparently as possible, Dark Souls is just too complex and deep a game to have a coherent guide of.
It completely fails against the more important details, speaking to you as if Dark Souls is a walk in the park, assuming you won't have difficulty in following its instructions, therefore becoming no help when things go wrong.
A case in point: there are locations where enemies have the ability to curse you. If you've gotten far enough to know what this means, you'll know it's a nightmare! Once cursed, whenever you die, you'll keep reappearing with but half your health, with the only solution but to travel to the other end of the map and buy the neccessary item to lift it.
The book just assumes this won't happen to you (which it will). Does it tell you 'if you get cursed, go to y to meet x to buy z? No, you'll be flicking through various pages finding the where, how and what. You meet the right seller earlier on, and the book doesn't even acknowledge he sells it. If I wrote this book, I would've recommended anyone to buy a couple to save you possible hours of frustration.
There are other times where the authors ought to have blatantly told when to do objectives, what to buy, and where not go yet, but either ignores, or obscurely leaves it up to you to decide.
Presentation wise, enemies, bosses, and friendly NPCs are explained in separate chapters, so you'll be flicking from one side of the book to the other constantly, which I found personally to be quite a chore. When I wanted to find out how to summon NPCs for bosses, I had to go to two pages on opposite sides of the book, to still not get a clear answer, so ended up finding the answer on the net.
Also, maps don't explicitedly tell you where to go (lines or arrows would've be nice), and because the level design in certain areas are so convoluted or overlapping, it's impossible for simple overhead pictures to make sense of them anyhow.
And the walkthrough is near useless in explaining how to beat bosses. They try their hardest with several pictures, but these monstrocities are too animated to depict accurately in stills.
Honestly, I've had more help from free guides on gaming websites, videos on youtube, and tutorials on the Dark Souls Wiki site. They're clearer to understand, have more useful pictures, and seem to require less time finding the information you want. I would highly recommend you do the same. Especially as there have been times I've noticed, on Amazon and similar sites, people are trying to sell this book at a ridiculous price. It's not worth it.