Well, the evidence of extortion is just too big to be ignored. It's not hard to find. I just searched for [yelp extortion] and turned up about 50,000 articles. Now accusations are not the same as being guilty for sure. So here is why I believe it.
1. The fact that so many people's stories are similar. These are people who are not in contact with each--how is it that they all have very similar experiences with Yelp management? It is hard for only 2 criminals to agree on a story to tell, much less hundreds of people.
2. Much more damning is my personal experience with Yelp. One of my reviews does not show up unless I'm logged in. (Evidently, they are smart enough to not filter out your review when they know you are looking.) When it was 5 stars I could see it, but when I updated it to 3 stars, it magically got dropped from the list of reviews! FISHY. And others have experienced the same.
So I'm pulling the plug, and deleting my account. Who knows if yelp will honor my wishes and actually delete my reviews?!
P.S. For those of you who think "Well, it doesn't affect me so I'll keep using yelp" consider this: how many restaurants will you waste your money on because the ratings were manipulated?