The blog seems meant to complement and promote their textbook. Who would ever think to use a blog for such a purpose?
Random Observations for Students of Economics
I am the Robert M. Beren Professor of Economics at Harvard University, where I teach introductory economics (ec 10). I use this blog to keep in touch with my current and former students. Teachers and students at other schools, as well as others interested in economic issues, are welcome to use this resource.