A third gray area involves a variant of a cloaking technique that Fishkin calls faceted navigation. Faceted navigation means giving every user a customized page. There is nothing wrong with that if it is done to help the users, says Fishkin, but if you add a page intended purely to impress search engines, that falls into the gray area.
"It has gotten people into trouble," Fishkin says.
But the most visible gray technique is undoubtedly content farming, where a site posts large numbers of hastily written pages covering popular search topics, often containing little real information.
Google responded to content farming in February when it announced a change in its algorithm, called the "Farmer Update," that would reduce the PageRank ratings of sites that consist of little more than general text written around a search phrase, while improving the ratings of sites with original content and useful information.
"It did hurt most of the obvious content farms," says SEO Book's Wall. "But tens of thousands of sites were impacted, including structures -- especially some e-commerce sites -- that were not bad sites but had certain characteristics in common with content farms. Algorithms have false positives, and the Web is so huge that an algorithm can't always be right. Three months later, none of the sites that were hit have recovered. We are still on uncertain ground and can't say, 'Here is the footprint of the change, and this is how you get out of it.' "
One of the leading owners of content farms, Demand Media in Santa Monica, Calif., told Reuters in May that search engine referrals to its eHow site fell 20% after the change, and overall page views fell 12%. According to the article, it announced plans to switch over to higher-quality content, with commissioned articles from professional writers.
Look at the long term
In the end, white-hat SEO is, for most sites, the most practical way to assure yourself of long-term success in rankings.
But that may not be as limiting as it sounds. If you eliminate the obvious black-hat and gray-hat approaches, "white-hat SEO is nearly every other marketing, branding and traffic-growth activity or operation on the Web, including millions yet to be discovered," says Fishkin.
"If what you are doing requires things like expensive research, or building and leveraging real human relationships, and reflects those relationships, then it is generally considered white-hat," adds Wall. "White-hat concepts will stay the same, but black-hat methods have to change constantly" in order to stay ahead of Google.
"You might get minimal short-term results with black-hat methods, but the penalization of your website will outweigh that in the long term," Koller agrees.
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