Since I like to have my time well spent on trips,I usually do considerate research before going backpacking and I was really excited before going on this one. The problem is- there are very few guidebooks that are dedicated to backpackers and trekking. I've seen the "other" famous guidebooks on Iceland, but they all seem to be all about hotels and restaurants!
This guidebook, although definitely not dedicated only to backpackers, has the perfect combination and was great for planning. I found plenty of information on trekking opportunities including doing it on your own, operators, shuttle services, access ways and lots of "pearls" missed by other rushing tourists. I found their recommendations to be very close to the average backpacker's taste.
Of course, like all guidebooks, it had hotel/hostel info for different levels of budget and also popular attractions.
I found the list of attractions and best towns to stay to be very good.
I saw in another review that someone was upset about the fact that the book has no pictures and he asked how he was supposed to decide where to go with no pictures?. Come on! just Google the name of whatever sounds nice or interesting and you'll see better photos than any guidebook has. Another advantage, part of it due to the fact there are no photos- the book is really light-weight (around 300g or less I think)- all other guidebooks are around 0.5kg or more!, again, just what a backpacker needs!
Spending the last few days in Reykjavik, I found the info on dinning, shopping and museums very helpful and precise.
To sum it all- I would like to mention that I was traveling and trekking around Iceland for a full month, only by hitch-hiking (yes, Iceland is probably the best place in the world for a solo hitch-hiker), and I found everything I needed in that book.
What I would add: More maps, especially of parks and trails. And well, It wouldn't hurt to add a FEW pages with photos, I guess most people would like that.
Thank you Frommer's!