Google Algorithm Updates for 2012
With the constant changes that occur on Google’s Algorithms, it is certain that the SEO and link building will be harder compared to what it was like before. With these changes, it becomes essential that business owners and individual site owners look at their websites and adjust their SEO strategies accordingly.
Understanding these Google algorithm updates and how they impact your rankings in Google’s search results is essential in defining your SEO strategy.
Source: SEOMoz Algorithm Change