Earlier this year, Google (news, site) started dealing with content spam and low-quality sites in its search results by crowdsourcing quality control and by updating its algorithm. Initially rolled out in the US, the algorithm update is now gradually being rolled out to Google data centers in the rest of the world, and search analysts are reporting how the new algorithm affects sites depending on type and content.

Dubbed "Panda," the algorithm update has significantly affected certain sites to the point that some webmasters are reporting traffic declines that are essentially driving them out of business. Also called the "Farmer" update (as the algorithm change targeted content farms and low-quality sites), the Google update initially rolled out in US data centers last March, where the brunt of the impact was felt. This week, Google's UK data centers are already running the Panda update, and search analysts have posted their findings.

Big Losers: Content Farms, Affiliate Sites, Price Comparison Sites

According to Search Metrics, the biggest losers in the UK with the Google algorithm change include content farms, affiliate marketing sites and price comparison sites. These include some of the bigger sites that used to be at the top Google results in their respective niches, such as eHow UK, reviewcentre.com, dooyoo.co.uk and Microsoft's ciao.co.uk, which has a standing complaint against Google with the European Commission.

At a glance, most of the domains that have lost the most visibility (up to 99.7%) are sites that either create content based on search demand or sites that repurpose content from other sources. However, some sites that push original content are also part of the losers, including technology blogs Pocket Lint, Tech Radar, RegHardware, PC Advisor, Computer Weekly and IT Pro Portal.

Ciao UK Search Performance

Pocket Lint founder Stuart Miles tells the Guardian that the update does not necessarily target only sites with non-original content, although it is believed that the site was penalized because of its  use of redirects on affiliate links.

We put out all original content. I could understand it if we copied and pasted everyone else and were a massive aggregator of crap. But we don't and we aren't. As a small publisher, we're always trying our best to bring good stories to the table."

Big Winners

The Google algorithm update is considered a "zero-sum game," though, as not everyone loses out when Google does updates. Some sites have seen increased visibility in Google UK searches. These include domains that attract a lot of page views, such as popular blogs, newspaper sites, blogging services and social networks. WordPress, TechCrunch, YouTube, and eBay UK have gained visibility benefits from Panda.

Is Google Shaping Up?

Google's market share is on the decline, with Microsoft Bing-powered searches -- which include both Bing.com and Yahoo! search -- being on the rise. Bing is currently enjoying a 30% market share in the US, with 14.32% being from Bing.com itself. According to Mashable's Christina Warren, Bing-powered searches might even overtake Google by January 2012 if it is able to sustain this growth.

The latest algorithm update might be a reaction toward a perceived decline in Google search quality. But apart from search, Google is also setting its sights (again) on social, with its inclusion of social-recommendation engine +1 in searches. Google is putting its hopes on social to the extent that the company is tying employee bonuses to the success of its social strategy. It would surely be a shakeup if Microsoft were to overtake Google in search, and Google were to overtake Facebook in social.