A recent interview with Josh Cohen, who is Senior Product Manager of Google News, shows how user behaviour can affect ranking in Google News.
This approach is also used by TrustRank, as part of its complex formulae, and it is inevitable that more and more user behaviour traits are likely to be included in ranking algorithms in future.
For instance, each user conducting a search is (hopefully!) a human being. Therefore, a user can easily spot from certain clues when a link is inappropriate for their needs. This may be because it is an example of spam (it is big business getting spammy results to the top of the SERPs), or because it is from a publication which the user does not trust or value. It may be that it is irrelevant to their search – common where there are different meanings for terms eg in specialised industry sectors, different cultures and so on.
Conversely, users may always click on articles from certain publications, or with a certain type of headline, and so on. Google News is aggregating this user behaviour data over time to ensure the news service delivers what searchers are seeking.
Watch out for more and more user behaviour criteria in all SEO. Build your brand so that users learn to recognise and associate it with quality content. Build your content so that users return over and over again for your opinion. Learn from your own traffic stats. Analyse the popular pages on your site, run multi-variate testing to see what works best for your audience. Listen to your users – surveys, feedback, polls.
People are fickle – they may not always do what you want or expect, but it is important to remember – the customer (read: website visitor) is always right!