Yelp seems like another business that would have worked much better for the users as a nonprofit ala craigslist (I know craigslist isn't a nonprofit but it's more or less run as one.) See the sporadic bursts of drama about businesses being forced to buy ads on yelp to influence reviews [1:3]. You have to wonder what they're going to do to get enough revenue to support their desired $1-$2B valuation.
As a small business, we have never been extorted directly (noone has said 'we will bring your private reviews public'), but the percentage of filtered reviews across different small businesses is RIDICULOUS.
All of our reviews are from legitimate customers and we've reached out to Yelp to try to understand their algorithm. They assure us that everything is 'proprietary' and they 'cannot divulge secret information.'
We previously showed up to 36 positive reviews at one time, at which point we were seeing huge foot-traffic from yelp. Since then it has more or less dropped off.
You're probably not gaming yelp correctly. You can't ask your customers to review you because they'll be filtered since they'll only have one review.
You need to get more Yelpers to your business. If they're elite, that's even better. You obviously have a good product because you have 4.5 stars, so it's just a matter if getting those elites to your place.
I have friend who works hard to cater to the elite Yelpers. He thinks that's the key to his success. I don't know if it does get him more foot traffic though. Anyway, It was a lot of hard work, even though he had a great product. He finally got his place to the magical 4.5 star mark with over 125 unfiltered reviews.
But you're forgetting that this time it's different. With social networks, you don't need a business model. Because of the network effects, and increasing number of mobile devices, they will be able to leverage the cloud and produce real-time location-based analytics. So, as you see, Yelp doesn't require a conventional business model to have a multi-billion dollar valuation.
[1] http://www.cbsnews.com/8301-505123_162-42744374/inside-yelps...
[2] http://www.eastbayexpress.com/gyrobase/yelp-extortion-allega...
[3] http://articles.nydailynews.com/2010-03-20/news/27059507_1_y...