Zagat gobbled up by Google for undisclosed sum

Google announced today that it had gobbled up Zagat, a restaurant-rating guide co-founded in Nina and Tim Zagat in 1979. Originally covering only New York City, the Zagat empire has swelled in recent years, ranking eateries in hundreds of cities on its familiar 30-point scale. In a post on the Google blog, exec Marissa Mayer said that Zagat's user-generated reviews would be a natural fit for Google.

"Moving forward, Zagat will be a cornerstone of our local offering – delighting people with their impressive array of reviews, ratings and insights, while enabling people everywhere to find extraordinary (and ordinary) experiences around the corner and around the world," Mayer wrote. (In a separate letter, the Zagat co-founders called Google "the perfect home for our content.")

So what does the acquisition mean for the tech world at large?

Well, for competitors such as Yelp – which also ranks restaurants and bars on a sliding scale – it will mean a gigantic headache. It could also pose problems for online coupon sites Living Social and Groupon. The Google-Zagat pairing will be "huge" for Google Offers, writes Adrian Covert of Gizmodo, because Google will now be "able to back up its discount offers with testimonials and ratings about the food purveyor in question."

But Google's real target may be the growing mobile advertising market. Over at Reuters, Lucas Shaw points out that with Zagat, Google has bought itself just one more platform on which to sell adverts. "Combining local content with search and maps enhances the possibilities for location-based advertising, which is key for Google," Shaw writes.

Many questions remain, including the future of Zagat's print-publishing arm, and the paywall which surrounds a lot of Zagat content.

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