Out of all the strategies that I'm using, article marketing and article directory marketing is where I'm getting most of my traffic (and sales) at. I'm getting REALLY GOOD results right now on this method (which is only natural since I'm running a content creation business).
A key factor when doing this type of marketing is to make sure that you don't only have good content, your content should also have a certain level of psychology added to it. Always remember the 3C's (content crafted to convince) when writing your articles or If you'll have it outsourced.
Luckily for me, I have experienced writers on my team who can make compelling articles.