I think there's value in both honestly. If I'm traveling to Germany and I'm sitting in the middle of Munich looking for a quick and decent bite to eat near The Residenz, something like Yelp! has a lot of value. Even if the reviews are in German I can piece together enough of the language, and use the "Star" system well enough, to find someplace decent. I get to eat a fair to good lunch and everyone wins. If I want to find a nice restaurant to take my wife later that evening, something more like Zagat's or Fromer's would be more appropriate. Munich is a big city, the ability find and read reviews of particularly well know or popular restaurants, in my own native language, is useful.
Now back home, I'd be inclined to use Yelp! for either situation. After all, I know enough about my own city to give me a starting point for finding good places. When I'm traveling though, particularly when I'm traveling somewhere that English isn't the native tongue, editorial reviews have a very real place in my planning. Hell, even here at home I use a certain amount of editorial content. I watch the The Phantom Gourmet I've been known to check out restaurants they recommend.