I bought this guidebook for a Jan 2012 trip, mainly because it was the newest edition of a Nicaragua guidebook (Nov 2011), so I assumed it would have a lot of up-to-date information. Boy, was I wrong. While I could forgive constant inaccuracies on hours and addresses (let's say these things change, although probably not that quickly), my main problem with this book is an unacceptable lack of detail and inaccurate & severely lacking maps.
Lack of detail: this book has only very brief and general descriptions of only main attractions. This is absolutely NOT a book for a backpacker or traveler who wants more of a trip than just some pretty pictures. How can you learn about your options if a description of a huge volcano with many many hikes is just 1 paragraph? This is how this book is written.
Also close to no information on transportation. Bus stations are not marked on town maps (unforgivable), so the author assumes that readers will take cabs everywhere. Most bus stations in Nicaragua (except Managua) are at a walking distance from town centers / attractions, but you wouldn't know it from this book. Maps have hotels, restaurants, and a few main attractions marked on them, but not one bus station, tourist information, supermarket, or post office. These maps are flat out horrible and far inferior to Lonely Planet, for example.
Regional maps are severely lacking, too. You only get general maps of surroundings of main tourist areas. I ended up transferring chicken buses on the way from San Carlos to Managua (a road less traveled, but still traveled!), and I had no idea where I was on the route, because there is no map of the region in the book!
I will never buy a Frommer's guidebook again. Maybe this is acceptable for someone going on an 100% organized group trip, but if you are in any way an independent traveler, or just like to read more than a paragraph about a major attraction, this book is horribly inadequate.