The facts are in: At least 80% SEO companies employ directory submissions as a way of increase link popularity and rankings. But the question begs to be asked, are directory submissions totally worthless or do they still hold any value?
Simply put, not all directory submissions are worthless. If you think about it, even the crappiest of directories do provide link juice, although it is very little.
A rule of thumb in this situation is: If a directory is not actively managed, or if anyone who pays or submits URL to a directory gets accepted, then the directory is not valuable.
Think about it this way, if a directory is not actively managed, it falls prey to spam. Spammers are notorious for seeking venues to exploit. They have a way of knowing whether a certain directory has effective spam controls or not. To be honest, any person with little common sense can check out a directories content and get to know whether it will be OK to spam there.
Also, if anyone is able to get listed in a directory, the directory is crap because…. well… everyone can get listed in it. This creates a problem as I am sure you would know.
That being said, there are directories out there which provide users with considerable link juice. But the inclusion fees for such directories can be quite hefty. In my opinion, the inclusion fees is necessary in order to deter spammers from submitting URLs to such directories.
Here are some examples of good directories:
1. Yahoo Directory – Paid inclusion, $299 (I believe).
2. Business.com – Paid inclusion
The point is, if you need link juice when submitting to directories, you need to pay a fee. Most (or all) free directories have little to know link juice value. So if you submit to them, your link popularity will increase, but I doubt that your rankings will increase.
I have never really bothered to submit to any directory, paid or otherwise. The reason is that for the hassle that you go through, you can get someone to provide you links from high quality websites (which are not directories).
Any websites which provide good free content and have a high PR can be worthy of a link.