This is a question that many people are asking themselves. This is actually an older argument, between people who think that the more links you manage to gather for your website the better and those who say that this might trigger a red flag in the eyes of the search engines.
So how should you submit your articles? Well, it really depends on the purpose for which you are doing this. There are basically 2 situations and 2 courses of action consequently:
1. You want certain keywords to be as high up as possible in the SERPs: If this is the case, then you should probably be careful before submitting the same article to hundreds of article directories. The best strategy in this case is to constantly submit an article (one different article each week, for instance), to the best 10 or 20 article directories. Here's a short list of a few of the best article directories which will give good relevance to your articles:
1.
www.ezinearticles.com
2. www.goarticles.com
3. www.articledashboard.com
4. www.tntarticles.com
5. www.articlebase.com
6. www.articlepros.com
7. www.webpronews.com
8. www.articlealley.com
If you want to be absolutely sure that this will greatly help your SEO campaign, you may want to spin your article and make it unique for every article directory you are submitting it to. Also, you may want to change the anchor texts of your backlinks likewise. For instance, a backlink on ezinearticles.com could have the anchor text “dog food”, while when you submit the article to www.tntarticles.com for instance you could change it into “best dog food” or similar terms. I know this requires more work, but it's definitely worth it.
2. You don't care about the SERPs, you only care about Page RankThis can be true if you build a website with the purpose of selling links, a web directory for instance. Usually, you don't need terms in top 10 on Google if you have a web directory. What you need to do in this case is brand your website and get as many backlinks to it as possible.
If this is your case, then submitting as many articles to as many article directories as possible is the best idea. You don't have to spin the article, you can send the same copy to all the directories. The best option is to send a fresh new article each week. The number of backlinks to your website will skyrocket and your Page Ranks accordingly. Then, if you manage to get a PR of 5, you can start selling links for a pretty good price.