According to google, the have now completed their caffeine infrastructure. Based on what I have read on places like WMW and Matt Cutts blog it sounds like this is more of an infrastructure change rather than an algorithm change, though there was what was known as the Mayday update. Here is what I been able to make out of it so far:
The Mayday update brought about changes to the algorithm with regard to long tail keywords. Apparently they are looking at more "quality factors" when it comes to deciding if a page should be ranked well in the index for a long tail keyword. Interestingly, at the time of this writing Dogpile, Altavista and Bing rank higher than Google for the keyphrase "search engine". Also it is interesting that "search engine" does not appear in the title tags of any of these search engines. So it leads one to ask what kind of "quality factors" come into play. Obviously, Dogpile and Altavista are very old, so domain age may play a role there. Also, some have reported seeing more domains in the SERPS and fewer internal pages.
Google Caffeine is supposed to be more of an infrastructure allowing google to separate different types of content such as video, images and web pages, as well as be able to to more quickly access ranking factors for specific pages or content. Aparently, the "big daddy" update was limited in the number of factors that can be accessed, and caffeine takes care of this. They also talk about freshness and speed of updating their database for both content and "page factors". They also mentioned updating for changes to pages more quickly.
What does this mean to directory owners?
Because Google notices changes more rapidly now, they are going to know if you are keeping your site updated. Are you going through older links and articles and making sure they have good titles and descriptions and are still working? Are finding empty categories and adding content? Continuing to improve quality over a period of time and having a proven track record for doing that is going to be increasingly important. Also, many have found that adding links to twitter and tweeting about new features or pages in their directories has helped get content indexed and ranked, because Twitter plays well into google's plan to index content as it happens.
Interactivity is another great way to insure content is getting changed throughout your site over time. Since google can find changes faster now, and seem interested in content that is updated, encouraging communication on your site is going to be important. If you haven't already, we highly recommend use of the Disqus plugin. It integrates with Twitter and Facebook (and other social media), and at the same time allows for spam guarded communication to take place on your site, so people can add content about links or articles you have already published.
We are also finding that there is even more reason to address the situation with stub pages on directories. Having pages that serve little purpose is becoming a real problem, and all the more reason work through your site and make improvements.
Staying up to date with the latest developments and continuing to improve your directory should help you stay on top, and we look forward to helping you. Feel free to pop into our forums and take part in our conversation (and maybe provide us with some fresh content!).
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