On October 5th the whole SEO industry held its breath and the owners of many websites pulled their hair in disbelief as their sites vanished from Google's natural search results. The culprit - the Penguin. Google decided to roll out a major update to it's black-hat SEO banning algorithm. The update was officially announced on Twitter by Matt Cutts (@mattcutts), the lead of the spam-fighting team announced that Penguin 2.1 will only affect about 1% of the search engine's results. If you calculate that into absolute numbers - about 400 million web pages went down in ranks.
Why is my website gone?
The first version of Penguin was introduced in early 2012. Its aim was to push down pages that have been promoted by low quality links (SEO directories, pretzel pages and artificial manual linking vi anchor texts), pages which are not updated in a regular manner and those that don't contain original content. About that time everyone was afraid that Google will over-optimize the algorithm. The new release seems to focus on the same factors but the impact is much stronger. The mentioned above 1% of results seems to be strongly condensed in the first few pages of results. Because of the world-wide red bar charts in SEO site statistics - October 5 has been announced the "Red Saturday".
Let's be honest: search engine optimization is an attempt to fight the search engine's algorithms. It is not uncommon that the taken measures brake Google's spam prevention. There's a big pressure to provide visible results in short time, but these strategies always fail when there's an algorithm update. The trick is to promote the site with valuable content from valuable sources over a prolonged period of time. You should at all cost avoid link-directory clusters with anchor linking and link-bots that create content from your site's meta-tags. Provide value with content - and you'll be rewarded.
We can categorize the new Penguin's impact into two groups: sites that have dropped "only" a few pages in the results and sites that have dropped over 100 positions. If you're in the first group then there's no reason to panic: just cleanup all the junk links and soon your site should climb up. If you're in the latter group however you should consider a remap of the site's structure or maybe even a new domain name (with updated content!).