New York is imposing fines on 19 companies accused of writing fake reviews on behalf of their clients. This is an interesting move as local businesses raise concerns over the validity of the reviews of their own businesses vs. their competitors.
http://www.theguardian.com/world/2013/sep/23/new-york-fake-online-reviews-yoghurt
In the past, some have speculated that sites such as Yelp were purposefully pushing negative reviews to the top in an attempt to extort local businesses to use their paid services. However it appears some of this discrepancy was being caused by third party companies engaging in this practice outside of Yelps control.
http://www.theguardian.com/world/2013/sep/23/new-york-fake-online-reviews-yoghurt
In the past, some have speculated that sites such as Yelp were purposefully pushing negative reviews to the top in an attempt to extort local businesses to use their paid services. However it appears some of this discrepancy was being caused by third party companies engaging in this practice outside of Yelps control.