The site is simplicity itself. Users write reviews of local shops and services, either anonymously or using their Yelp profile. It works pretty well, there's some astroturfing from businesses looking to up their own credibility but when you've got a couple of hundred reviews for something it's difficult to outweigh bad reviews with phony ones.
But it appears there might be a downside to this. One San Francisco user is reporting that a bad review of a bookshop led to some increasingly annoyed messages from the owner.
""You are too much of a pussy to come in here and speak to me directly. Goodbye pussy boy and I will be contacting your employers," was one of the messages (the whole set can be seen here).
However, the situation got rapidly worse.
The user, Sean C, told V3.co.uk that he received a knock on the door of his home and opened it, assuming it was a next door neighbour. An strange woman tried to push her way into his house and after a serious struggle he got her out of his home and called the police.
"It's definitely the craziest thing that has ever happened to me.
"I have a handgun in my home and she is lucky that I wasn't armed at the time as things might have turned out very differently for her. I'm just glad that nobody got seriously hurt."
The woman has since been arrested and Sean has successfully obtained a restraining order against her. Nevertheless the exact details of how she managed to get his home address are unclear.
User generated content is going to be key to the future of sites like Yelp. While in the past there have been reports of people acting badly over reviews this is the worst case I've come across.
This won't of course stifle sites like Yelp. However, questions need to be raised about the true level of anonymity posters can expect from sites like this.
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