So – what kind of sites were hit hard? During my investigations, I observed the following recurring patterns. Additionally, these patterns were supported by data from Matt Hepburn's set of sites as well as the sites that are owned by clients and for which I provide SEO services: • Sites whose home page EMQ ranked were hit by the EMD Update if the home page was overoptimized – the title contained the search term, the search term was in the meta tags, the H1, H2, and H3 tags, and so on. Also, if the keyword density of the search term was over 2.0%, the site was nearly always also hit by the EMD Update. • Sites with more than 60% of all links pointing at the EMQ ranking home page were hit especially hard. Having a large percentage of all links pointing to the home page and very few links pointing to each of the other pages of the site seems to be used by Google as a key signal for abuse of the EMD boost. • Sites with more than 40% of all links being dofollow also were hit by the EMD Update. This may very well be an indication of a test Google is implementing now for the EMD Update, if it is found to be effective in improving the search results, this factor may in the future be applied to all sites ranking for a search term, not just EMQ rankings. • Sites with ten or fewer indexed pages and that EMQ ranked were also hit by the EMD Update. This may simply be a coincidence, since Google is already actively reducing the ranking of smaller sites designed to rank for only one or a few keywords. • Finally, sites were hit by the EMD Update if they had more than 30% of all back links carrying EMQ anchor text or anchor text containing a strongly related LSI keyword. This also was a key indicator for a site-wide EMD Update penalty. Just for clarification, “being hit by the EMD Update†means that the site lost ranking of at least 10 positions (e.g. dropping from page one to page two or further) for a majority of the tracked terms.
Thanks for sharing these useful information since I didn't know many of them.One of my EMD site also hit by that update.