From what I understand, adding content to my site via articles will certainly open open the doors to those pages getting indexed and generating traffic for long tailed terms. But lets say that my site is for Organic Fortune Cookies. Lets say that it ranks for Organic Fortune Cookies, but its number ten. Lets say that I write an article on Healthy Fortune Cookies (because this too is part of my target market), and I add it to the site. "Healthy Chinese Cookies" IS related to Organic Fortune Cookes, and in some ways its synonymous. If this page ranks within the SE's, will it help my MAIN page's rank for Organic Fortune Cookies? What if the keywords are totally different within the article and subpage.. btu its related. Will it help the main page's rankings for the main terms? I hope I made myself clear here. Sometimes the simplest things are the hardest to explain
I thought most of the article dirs now a days are using nofollow tag... so..most of the links don't help in increase your PR.. but they give you some traffic...