Why would you get a guide on how to play a singeplayer game? A roleplaying game? Doesn't that just ruin the fun of it?
Never seen this guide, and don't know whats in it, but please tell me what you get out of it...

The hardcover version, as a physical artifact, is beautiful. Some people, like myself, are book lovers, and would much rather have an expertly published book to represent the game than some useless game box or cloth map.
Also, the amount of information in the book is staggering. You have no idea until you open it up. This game is on such a higher level than any other game... and you really understand this when you're reading the book. People always associate guides with walkthroughs, but the walkthrough in this guide is almost an afterthought. The guide is just massive, and contains every single thing that's in the game.
The Oblivion guide was like a bible, and this one for Skyrim, even more so. It's almost an essential purchase for Skyrim enthusiasts.