To paraphrase, he said that your blog is your “homebase.” This is where you ultimately direct people. On the other hand, services like Twitter, Facebook, LinkedIn, etc. are “outposts.” The purpose of an outpost is to connect with people that otherwise wouldn’t find your homebase.
This makes sense to me. At least several times a week, I get Facebook messages from people who say, “I stumbled across your blog on Facebook.” So, for now, I guess I will keep my account open. Personally, I find Twitter so much easier to use and more rewarding—and certainly less annoying.