Since I'm only on FB and no other social network sights, I don't get much traffic to my blog... so I'm going to test this:
<a href="http://www.freewebdirectories.org">free directories</a>
and this one:
<a href="http://www.freearticlesubmission.org">Article submission</a>
If I notice a huge difference I'll report back, in case anyone else wants to try it.