Google Penguin 2.0 update, which was rolled out on May 22 2013 is just the evolution of its already existing algorithm that filters the search results. However, Google believes it as a massive update that will strongly affect the webspam.
When Penguin was first released Google pointed out that Black-Hat SEO techniques won't work and content of the websites should be for the audience and not for search engines. What people do is use SEO tricks to gain ranking and come up in search results but these are not helpful for users, as they do not get genuine results.
Those websites, which target keywords and use them in anchor text, signature in comments and stuff them in a page are being penalized heavily. These websites try to rank for a specific keyword by such practices. It was possible before but now Google is becoming more strict towards it. They are focusing on providing quality results up in the search engine and filter the rest.
Then there is paid linking, which the Penguin 2.0 is specifically targeting. It has been under scrutiny before but now it has one up the thing. It is closely watching every link, the websites from the link is generated and the websites to which link redirects. If the link is sponsored, both the websites will be punished. If the websites from which the link is taken is spamy or is flagged off, both the websites will be punished. And if the website to which the link has redirected has nothing genuine on it to offer and is just targeting the keyword or link building, again both the websites will be punished.
Duplicate content or content linked to multiple URLs are also being penalized. This affects the article marketing sites. Like all other things, it has been there before as well. But now content featuring anchor text that leads to same article is also under watch. Guest posts are legitimate but posting at a low quality websites just for the backlink won't help.
Major drop has been seen in many websites all over the world and it indicates how many websites in the eye of the Google are carrying out web spamming. Google has given a feedback form for people who want to report a spam websites and also for those who believe their ranking has been unfairly degraded.
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