TopRank has maintained this list for a while: http://www.toprankblog.com/rss-blog-directories/
Tips and Tactics for Amplifying Your Content
6/20/2014 Content marketing should never be approached with a "set it and forget it" mentality. It needs to be structured and shared in the right ways, and in today's Whiteboard Friday, the folks from Add3 are here to show you what that means.