im new in seo field. i know few more about directory submission.mostly people use directoy submission to submit there site but they dont know there disadvantage.
The Only disadvantage of directory submission is that search engines take lots of time to cache them.
If you have the SeoQuake toolbar, you can check real-time the last time the page was cached, and include your site if the page has been cached recently
Backlinks from directories or any other sites are the same. For sure some links weight more than the others. But backlinks either give you nothing or something...but won't take anything from you
here are some disadvantage of directories submission: (free submission) - wait too long to be approved - easy to be removed - hard to be aproved (or never be approved) - don't have quality back links - (any one know others ?)
If you donot believe in directory submission just forget it. Every thing has some time to taste - it may be wrong to term as disadvantage.