Mortimer Adler's ideas are kept alive by the Center for the Study of the Great Ideas, which has a web site and a blog.
The Great Books Academy Homeschool Program (and its Catholic version, Angelicum Academy Homeschool Program) seems to be the most thorough of the "great books"-centric education programs designed for all education levels.
Thomas Aquinas College in Santa Paula, California, is another major proponent of "great books" education besides St. John's; its web site offers an explanation of the role of the Great Books in its curriculum and its four-year plan.
Shimer College, formerly tied to the University of Chicago, has maintained its "great books" focus: see the Curriculum page of their web site.
St. John's and Shimer, unlike Thomas Aquinas and several other "great books" colleges (such as Gutenberg College, the College of Saint Mary Magdalen, and the Thomas Core College of Liberal Arts) are secular, as Adler and Hutchins preferred.
Countering arguments to these kinds of programs--old and new, respectively: A Critical Appraisal of the St. John's College Curriculum by Sidney Hook and Why the Great Books Aren't the Answer by Patrick Deneen.
Another interesting article: Who Killed Homer? by John Heath and Victor Davis Hanson.