A good summary on Google’s latest update: Penguin

SEO and the Flight To Quality | RKG Blog.

The Panda update puts a premium on original, high-quality content and clean, canonical sites. Duplicate content can be a bigger problem now than it was before the update hit. The rule of the day post-Panda is a ‘less is more’ strategy and a focus on user engagement. Now Penguin puts a premium on natural links and anchor text. In early 2011 we preached that SEOs should quit obsessing on anchor text. For those who followed my advice back then, congratulations. You’re well positioned to take marketshare from those who may have taken shortcuts in the meantime.