I was at a Future of Digital Marketing Conference a couple of weeks ago. As expected, social media was a big theme. Mirko Behnert from Venere showed an interesting slide outling the two 2 sides digital marketing. Whilst traditionally, one side is industrialized and focused on data and optimisation which works well in a campaign-driven environment where tiny changes can make an enormous difference. The other side is less predictable and requires some different skills to engage. The results are not always predictable.
On this same subject, take a look at this video which brings the different roles that each side of the brain plays to life (literally)
http://www.ted.com/talks/jill_bolte_taylor_s_powerful_stroke_of_insight.html