Directory submission- Directory submission services is very important to enhance your website popularity. If your are submitting niche directory and these are based on geo-location then your website will definitely improve in that particular region........directory can be reciprocal and one way link based....
peoblem is that people have not taken the time to write unique descriptions for their entries... this marks a good directory from a bad one, look for ones where the descriptions are lengthy and the internal pages have pagerank.
Yes directory submission is important for seo, But directory should not be spamming.Search engine like manual directory submission.