Korean search portals have become more social in recent years; can you explain how that would impact SEO/ SEM strategies?

According to KISA (Korea Internet & Security Agency), 61.3% of users from the age 12 to 49 Koreans are using SNS at least once a month. In 2010, social networks are covering the highest volume of impression of the online banner ads. 

Still social contents are not yet fully mature in Korea; it is much cheaper and easier to build trust through active engagement with potential customer. Don’t forget the ‘Law of Mind; from the book, the immutable law of marketing that it is better to be first than selling a better product. Social is part of SEM now in Korea market as they are in the same page of Search result page.