I was going to reply to the article-marketing thread from which I took the following quote, but as I wrote it seemed I was getting too far off topic. Basically the OP asked if article directories are good or not, and here's the reply he got:
I agree that article linking and related methods of link-building are not ideal (excluding spam, which goes beyond way beyond "not ideal" into "don't do it!"). However, I have yet to receive a satisfactory answer to the following question: If I have a site that exists to sell something, why would anybody link to me???
Somebody will certainly suggest that I create "a blog" or some "valuable content" in order to attract links. To see why this doesn't necessarily work in the real world, let's take an example.
Suppose I sell replacement batteries for business phone system cordless handsets. What am I going to blog about? The latest trends in replacement handset batteries? Who would read or care, much less be interested in linking to me, if I did?
Valuable content - let's see... At best, maybe I could create some kind of an easy-to-use chart that helps people match their phone with the battery they need. Maybe after a few months or years, two or three folks will link to me on their own and I can persuade a couple dozen others that my chart would benefit their site's visitors. How many of these links are going to contain commercially beneficial anchor text? Without that anchor text, do you really think I will be competitive in my niche?
I would like somebody to take the above example and show me how such a site could get ranked within 18 months for reasonably competitive keywords, attracting links only through "authentic" link building. Keep in mind that you're competing against people who've never heard of "authentic" link building, and instead are firing on all cylinders, using article marketing etc. Once again, I am not advocating the use of spam techniques. There are number of tactics, however, such as article marketing, which get dismissed as "unauthentic" but are most definitely not spam.