Generally we do the directory submission to get popularized in search engine or get initial back links. but you can not 100% relay on directories. For a website we need quality back links which is niche related and having good pr. I think blog commenting and forum posting will help you.
In my opinion, directory submission helps you to get quality back links. Quality back links helps to your website to get top ranking in major search engine.
Directory Submission creates a high quality back links for your website. It is process of submitting website to web directory after selection of relevant category to site submitted. The process involved section of directory, selection of category and filling of title, description, keywords, name and email to complete the submission process.
yes I also totally agree with other users Directory submission is good for creating backlinks for any website but it is not highly responsible for rank the sites.
Directory Submission is only step 1 for a good S.E.O optimization. After this, you need to make blogs, articles and forum. And make your website with high S.E.O score.