Mehmet Arap
1 A Fantastic Tourists' Guide
My wife and I recently went to Istanbul for a week with this book and Lonely Planet Turkey. This was by far superior for all of the sightseeing elements of the tour. The book is readable, clear, and provides pictures of many of the major landmarks and buildings of Istanbul so that you know what you're looking at; it also provides maps to major sites like Topkapi Palace and the Blue Mosque so that you can orient yourself. There are several interesting sidebars on Turkish history or customs that are fairly interesting.
The only drawback to this book is that is has only a cursory review of most of the restaurants and (especially) hotels in Istanbul; this is the only place where I felt that Lonely Planet was better in any way.
That said, I nearly bought a second copy of this book because my wife always was looking at it and I got tired of looking at the maps and text written upside-down. If you are only going to buy one guide for Istanbul, make this the one.
2 The best for Istanbul, the perfect DK guide
The maps are the most useful of any of the Istanbul travel books I have seen; although this book gives history and analysis, it is not too in depth, as the Knopf book can be, so that you lose sight of where you are. The tours laid out in this book contain references to small cafes and shops and restaurants that none of the others do. Portable enough to carry with, the drawings of such sites as the AyaSofia are excellent; it is pretty to look at, educational, useful and easy to carry. This 2003 version is very up-to-date on one of the most fascinating cities anywhere. Excellent book, wonderful city.