A WebmasterWorld thread has one SEO noticing that Google has started to purge their index of the free directory submission web sites.

He said that about 50% of the free directory submission web sites are no longer to be found in Google. I searched for a bunch and about 50% of my searches returned results and 50% did not.

Here is one example:

The big question to me is, is this new? Did Google just remove a bunch of these directories? Is Google going to remove more? What criteria did Google use to decide which ones to remove?

Forum discussion at WebmasterWorld.

Update: David Harry is analyzing data and currently after testing 500 directories and says 16% are delisted from Google. So a lot less than 50% but David is researching more and maybe if that list of 500 was increased to 5,000 it would be higher?

Image credit to ShutterStock for directory book