This guide up to this year was titled The Rough Guide to The Baltic States, which of course was highly offensive and ignorant to the people who live in Estonia, Latvia and Lithuania. Calling these countries Baltic States is pretty much the only time, these extremely friendly people will start to get a bit narky, and understandably so when it refers to their previous terrifying years of being occupied by the Soviets and the torture, genocide and misery associated with that. All of these countries have been independent for at least 10 years now and really don't need to be insulted by that kind of ignorance. When I was there last year and backpackers carrying the old covered books would pull them out to ask for directions while buying lunch or something you just cringed as you could see the insult on the faces of the locals. So at least The Rough Guide has changed the cover (although putting an old brothel scene is probably pretty offensive too). However even with the new brothel cover, you open the book to the first section Basics - Getting There and the first line shows the editors still haven't learnt a thing, with "From the UK and Ireland the most convenient way of getting to the Baltic States is to fly". The fact that they aren't aware of how taboo referring the Baltic Countries as Baltic States is, which is equivalent, well actually a lot worse to calling Canadians Americans, New Zealanders Australians, or Irish people British, does make you question just how many years ago did the writers actually go to these three countries. And therefore, how current and relevant is the information inside.
The information inside is a bit more current then the pre Berlin Wall coming down years, there's places to eat, places to stay but like all these sorts of guides, there's a heap more better places than listed inside. If you can't come across any other guide for this region, this book would be helpful in planning your trip and working out just which towns and national parks you want to visit. I would however get a copy of Lonely Planet Estonia Latvia & Lithuania (Multi Country Guide) instead as it does have a bit more information, and even though the latest was published in 2009, I don't really notice much more uptodate stuff in this Rough Guide. The Lonely planet guide also has chapters on Helsinki Finland, which is a short ferry ride from Tallinn, and Kallingrad Russia, which is also an easy day trip from Klaipeda. I didn't go to Kallingrad but found the Helsinki chapters very useful when I went to these countries in 2010.
The maps of the towns and cities are pretty much on par with Lonely Planet's. I wouldn't rely on either guidebook for hostel bookings, I'd go to Hostelling International, BUG and Hostelworld and other hostel booking websites to choose, read reviews by previous travellers and book your hostels before arriving.
If you're thinking of going to these countries but don't know if you should, definitely do so. The people are some of the best and most friendly locals you will ever meet. There's heaps of great towns to visit in each country but if asked to name two must see destinations in each country my recommendations of the best places are, in Latvia Riga with its great parks, old town and people. As well as the small town of Kuldiga with Latvia's widest waterfall next to a nice relaxing old town.
In Estonia you have to see Tallinn, especially it's medieval old town area, where again like Riga, the local people are so friendly. As is the picturesque southern town of Viljandi which is pretty much the only place the trains from Tallinn go. Viljandi has great castle ruins, a nice lake and is again just a really nice relaxing small town. Note you can't catch a train from Riga to Tallinn, you'll be bussing it on Eurolines or a more expensive company.
In Lithuania you have to visit Juodakrante and the numerous highly detailed wooden witch, goblin and other creatures huge wooden monuments in the hills behind the Curonian Spit town (you can do it as a day trip from Klaipeda but there's nothing much to see in Klaipeda). Kanaus is the best of the Lithuanian big cities, much better than the overrated Vilnius.