You missed the point completely. I'm going to have to listen to people obnoxiously reviewing their foodlive in the restaurant not the appno doubt using a louder than normal announcer voice. What's next, boom mics and soft boxes? (Joke) But seriously, a restaurant is for eating, not personal video production at the expense of other guests.
The videos are limited to a maximum of twelve seconds, definitely not enough time for a (worthwhile) review. The point is to get a quick view of the interior and ambiance of the place.
I don't necessarily disagree with your views in restaurants being for eating but it's sort of what smartphones in every pocket has done.
I read an interesting article on a restaurant that started getting bad reviews on the time it takes to. Get food to the table and that food often arrived cold. Because they had been around for over two decades they decided to look into it reviewing camera footage. Turned out people spend so much time in their phones before, during, and after ordering and even after good arrived, the conclusion was that service was slower due to servers having to come to the table repeatedly and food was cold because people were spending too much time photographing and posting it rather than eating it when it was served.
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Does Google have enough people actually reviewing to make it useful? Yahoo! had that for some time, but even that wasn't as much as Yelp.
It really depends. I've actually found google reviewers to be less picky (give higher ratings). There are also fewer ratings overall, generally speaking. I would think Boston and her surrounding cities would be a better than average reciew rate.
I guess it depends whether the number of reviews matters to you or not. Yelp also incentivizes really good reviewers (so people are encourage to review more) while google does not (to my knowledge)