I'm not entirely sure what I could say about this that others haven't, but I wanted to express my enthusiasm at least!
It's a beautifully presented book, for starters. Embossed covers, fantastic art and design work and it's a pleasure to have in your hands - Really, it's gorgeous. I can't emphasise that enough!
As for the cotent, it's a brilliant way of entering the world of Sanctuary. Or if you are revising or reminding yourself, wanting to explore and understand more, or simply want to heat your juices up for Diablo III - It gives you all the backstory, the story arc and pretty much all you need to know to be left ridiculously exited for Diablo III, and the continuation of the story.
The world of Diablo has utterly riveting and compelling lore, and this book perfectly demonstrates that.
Would you expect any less from a Blizzard product?
In summary, a beautifully presented, beautifully told piece filled that packs in a ton of the incredible lore of Diablo, and snippets of that which is to come.
Worth every single penny paid, and a lot more. £16 feels like a bit of a steal, to be perfectly honest.
To echo what everyone else has said : If you are fan of Diablo, get this. Get this now.