I came across a discussion today on "Socratic Classrooms". This particular commentator was describing how she sets up her lessons in such a way that students run the discussions and she used the approach, "Listen, Discuss, Collaborate". Apparently she has been doing it for years.
One of the strengths of this approach is of course that the responsibility for learning is now with the students, and as active participants they feel ownership which leads to enthusiasm, to depth and so on.
One of the weaknesses is that the quality of the discussions is related directly to the quality of the preparation. Some students will show a parasitic side and will attempt to take advantage of their colleagues' work and insights so the teacher needs a strategy to counter this.
As I write elsewhere, I like this approach and use it extensively with all levels, although it must be noted that some things may still be better covered using direct teaching, such as grammar.