After much testing I have found that article marketing still rocks for bringing in highly relevant traffic and leads that simply convert into better sales. The best part about articles is that other than your time they are 100% free to write.
In fact here is a study done using only a handful of article that resulted in traffic, inbound links and most importantly sales:
http://www.thekaizenbusiness.com/?p=174
A few tips to remember is avoiding duplicate content when possible and you will get the most amount of exposure to your articles by submitting to real ezine, newsletter and topical site publishers. Write up many resources or about the author boxes as well, at least twenty and submit a different one with each article.