Having a spent a month in Turkey in 2011 (primarily travelling off the beaten path) with this book as my main reference, I feel that I am more than qualified to review it. While this guide has a number of problems, it also has its merits. Much of the general information is quite accurate and their general advice proved itself to be extremely useful. For example, their description of the apple tea carpet salesman routine was freakishly accurate, and the entire time some guy was trying to sell me a carpet I couldn't help but note just how similar it was to what the book described. The environmental descriptions were quite accurate most of the way. By describing a lot of stuff off the beaten track in Turkey the book really encourages the traveller to actually experience authentic Turkey (which, as another reviewed noted, is not anything like Kusadashi or Kas.)
This is a good general guidebook and it got me around Turkey for a month. Do not be discouraged by the fact that I am now going to list a number of faults. Instead, use other resources to make up for these faults lest you get stuck somewhere. For one, the maps in the book are not always great. They are typically fine for more popular areas. The maps for Sultanahmet, for example, are just fine and you can find your way around without any trouble. However, the further you get from main tourist sites, the worse the maps get. The western sections of Istanbul inside the Theodosian Walls were nigh-unnavigable with the Lonely Planet maps because there were so many streets that simply did not show appear. I spent a lot of time lost in this part of town and was forced to resort to other maps and asking the locals. Another thing the book never mentioned were the obnoxious hucksters in the main tourist areas. While this is hardly a Turkish phenomenon, I did find them to be a lot more aggressive and irritating than anywhere else. Of course, once you're outside of any of the main tourist places you'll never see anyone like that other than children who seem to only know the word "money," and want some from you. Considering how often these things came up, the book's failure to mention them is notable. The book occasionally misrepresents historical sites as well. It claims that Perge, one of the most spectacular Roman cities I've ever seen (complete with a large theater, stadion, and Byzantine ruins on the hill at the end of the collondaded street) can be explored in an hour, whereas a day is more realistic. In a similar manner (and on the facing page) the book praises the ruins of Termessos. Termessos is in a spectacular location and is as easily accessible from Antalya as Perge, but the ruins at the site are unimpressive on their own, badly overgrown, and almost completely un-excavated. The book could also use better driving directions, information on parking, and general information on Turkish highways. I rented a car and learned as I went, leaning heavily on the GPS device the rental car company gave me. Some better general road maps and driving information could have alleviated a lot of stress, although I still managed to get around without too much trouble from the information in the book.
This is a good book. Although this review may seem overwhelmingly negative, I am merely pointing out some flaws so that anyone wishing to travel to Turkey with this book can make up for its defects with other materials. Other than these few caveats, this is an excellent book.