Google is always fighting to maintain diversity on their search engine results pages (SERPs). It has proven difficult over time to walk the line between offering searchers the content they want in easily browsable form, and keep the big established sites from completely dominating the results.
Matt Cutts, head of Google’s Webspam team, recently used one of his YouTube videos to talk about how Google is managing this, and highlight an upcoming change that will hopefully keep you from getting pages full of essentially the same results. No one wants to see eight results from Yelp when they are looking for a restaurant review.
The change Google is making is aimed at making it harder for multiple results from the same domain name to rank for the same terms. Basically, once you’ve seen three or four results from a domain, even over the spread of a few results pages, it will become increasingly harder for any more pages from that domain to rank.
If you don’t quite get what this means, it is easier to understand in context. In the video, Matt walks us through the history of Google’s domain result diversity efforts. It also shows how Google tries to manage bringing you the best authoritative and reputable search results without allowing bigger brands to form monopolies on the results.
You can see the full breakdown of the domain diversity history at Search Engine Land or in Cutts’ video, but basically when Google started out there were no restrictions on the number of results per domain. It was quickly apparent that this system doesn’t work because you will get page upon page of results from the single highest ranked domain. Then came different forms of “host clustering” which prevented more than two results per domain to be shown in the search results, but this was easily worked around by spammers.
More recently, Google has used a sort of tiered system where the first SERPs for a term are as diverse as possible, allowing only a few results from the same domains, however as you progress into the later search result pages, more and more results were allowed from repeat domains. Now, Google is tightening the belt and making it harder for those repeat domains to even get onto the later SERPs.