Since Google controls two-thirds of the U.S. search market, any tweaks to its search algorithm can have a dramatic effect. In late February, the search giant made a major tweak and according to the Online Publishers Association, a trade group of major media companies, that change shifted $1 billion in annnual revenues. Here's a look at the biggest winners and losers coming away from Google's tweak:

 

 

Losers

Mahalo.com

Jason Calacanis's human-powered search engine Mahalo.com lost more than 75 percent of its Google-generated traffic according to the software firm Sistrix. The site hand-picks links for a range of subjects and search queries with a goal of providing better, more useful information for search queries. However, because of the drop in traffic, Calacanis has had to lay off 10 percent of his staff.

Wisegeek.com

With the tagline "clear answers for common questions" WiseGEEK is a content farm with thousands of articles about everyday problems. Like Mahalo, WiseGEEK lost more than 75 percent of its Google traffic when the switch was made. Here's an example the of the kind of answers it produces. We typed in the word "sandwiches" into its search field:

Ezinearticles.com

Not sure if this one's going to be missed. Ezinearticles is a run-of-the-mill content farm with all sorts of "how-to's" and explanatory articles. It's also taken a 75 percent cut and, at first blush, it looks like it deserves it. One of the first terms that show up after typing in "basketball" reveals a "Tips on How to Get Better at Basketball" page filled with all sorts of tautologies and inanities:

If you learn to play basketball correctly, you will be a greater asset to your team, who will want you on the floor when it is "crunch time" and they need a bucket. Many people learn basketball incorrectly by playing street basketball, but you can show them up by making the right plays and smart decisions, leaving them wondering how to get better at basketball.

Associated Content

The Yahoo-owned site has long been one of the most controversial content farms due to its large size and acquisition by a publicly-held company. Similar to Ezinearticles, the site pays writers a small ammount to churn out a huge quantity of low-quality posts. In 2009, Slate's Farhad Manjoo called Associated Content "a wasteland of bad writing, uninformed commentary, and the sort of comically dull recitation of the news you'd get from a second grader." I'm sure he'll be pleased that the site just lost 75 percent of its traffic:


Winners

Demand Media

One of the most talked-about winners is Demand Media, a huge publicly-owned content farm that hasn't been significantly affected by the change. While its smaller properties Answerbag.com and Trails.com lost some traffic, it's biggest site eHow.com actually increased its number of page views since the switch.

 

Members of the Online Publishers Association

The OPA is a trade organization representing a number of media companies that create quality original content such as The New York Times or The Wall Street Journal. According to Pam Horan, president of the OPA, traffic to OPA member sites increased between 5 and 50 percent the day after Google tweaked the algorithm.  "This is good for the consumer, good for the Internet, and good for publishers of higher-quality content," Horan said. Here are just some of OPA members (see here for more):