Just got back from Iceland and took this guide plus the Bradt guide Iceland (Bradt Travel Guide). I liked this book, once I got used to the way it's organized. This is also the very most current Iceland guide book, and seems to be the only one that includes post-Crash information.
The book has many quality color pictures, printed on high quality paper. A nicer look than many others, but it also has good information.
That information is organized not area-by-area, and then town-by-town, but rather alphabetically, by topics that could be as large as the Western Fjords or as small as Seydisfjordur. However, that was the way we traveled: Hornstrandir, Western Fjords, Snaefellsnes, and then the Golden Circle. My wife liked the pictures and the text, I liked its overall "tone" and advice.
The book also includes a decent all-Iceland map in the back pocket, but that map is only good for planning, and is NOT adequate for driving around.
I don't regard this as the ONLY guidebook you should take: I would want a Lonely Planet or Rough Guide as well (for maps of towns and overall comprehensive treatment of the country).
One small note: on page 304 they say ferry service to Hornstrandir has stopped. That may have been true during the dark days in Fall 2008, but the boats are running on schedule in 2009.