February 27th saw Google announcing 40 changes that affect the quality of their search results.
This included the latest Panda updates, though they did not mention mention what the changes actually are. (Panda is a change to Google’s search results ranking algorithm that attempts to lower the rank of “low quality” sites and return high quality sites at the top of the search results. When Panda was originally rolled out in February 2011, it affected almost 12% of all search engine results.)
The other important change was to the their Link evaluation, where they have removed a method of link analysis that has been in place for a number of years. Incoming links have always been an important factor in determining the ranking of a website.
Other improvements included changes to the ranking of local results by relying more heavily on the rankings of the main search results, fresher images, increased size of the image index, more accurate detection of official pages, improved locally relevant predictions in YouTub.
You can view the full article on Google’s blog: http://insidesearch.blogspot.com/2012/02/search-quality-highlights-40-changes.html