Just returned from a trip to Europe and used this guidebook while in Paris. I usually go with Rough Guide's city guide books when I travel because I like how they break down the city in an area-by-area fashion. But I decided to try TimeOut's Paris guide book -- liked all the magazine-like layout and color pictures, history section, and other little layout info. nuggets (like Hemingway's favorite spots in town).
There's a ton of good info. in here like:
* excellent color maps in back (I didn't need to buy a streetmap when in Paris since it has all the major parts of the city covered).
* great concise info about attractions/restaurants/clubs/etc. with a pointer to the maps in back for location (loved this feature -- great time saver and prevents you from asking for directions).
* general tips on language, currency, pitfalls of Paris (like pickpockets! This little section could save you a lot of headaches -- the Algerian kids are real and they work just as described in here! I saw two kids at work in the Anver's Metro stop near Sacre-Coeur, but I digress....)
* the Trips Out of Town section was useful, but could use more precise information about what trains to take out to certain places like Chartes.
My major critcism of "TimeOut Paris" is the way the information is organized by these sections: Context (history); Sightseeing; Eat, Drink, Shop; Arts & Entertainment; and Directory (a vauge description that doesn't really get at what that section of the book is about). Instead of tackling each section of Paris and addressing these topics by city section, you have to search around the book for info., and that's a huge waste of time.
Lastly, as another reviewer already pointed out, check out Sandra Gustafson's Great Sleeps/Eats series and read them BEFORE you book and go on your trip. The accommodation and restaurant listings are skimpy in here. I also found TimeOut's restaurant recommendations hit-and-miss: I tried a Thai place recommended that was within walking distance of my hotel and was disappointed (great hip ambiance and people watching, poor service and skimpy portions), while another brasserie recommended in Monmartre was completely wonderful in every way.
The bottomline is that no single guide book will satisfy you on every level, but be sure to supplement this book with others as well as research on the Internet (check out Lonely Planet's web site and message boards).