Matt Cutts has posted a video encouraging webmasters not to use the article directories for link building. The video was in response to the question,
"Links from relevant content in article directories – Seen as good or bad? eg. I link my beauty website from a cosmetic surgery article on say, Ezine? Would you do that"?
Cutts said that an article is basically where you write 400-500 words of content and than include buyer information at the bottom of the article. You might have three links with keyword rich anchor text at the bottom. Anybody can use or download these articles.
The theory behind is that if somebody finds that article useful and puts it on the webpage, then you might get a few links. Cutts said that Google has seen that it often tends to be low quality stuff. There are instances where you get to see spammy content getting sprayed and syndicated all over the web.
Cutts said that going to article directories, just writing one article and syndicating it widely or uploading it to every site and hoping that everybody would download and use it on their website will not be really effective.
Google has algorithmic things that mean it will probably be a little less successful now than it would have been a few years ago. So, Cutts recommended that you should probably not upload an article like that.Matt Cutts Recommends Not to Build Links Through Article Directories!,