At various times in my career as a professor, I have participated in graduate-level courses in which different faculty appear for a day, a week, or a couple of weeks to talk about their general or specific research field with a diverse group of grad students. In my experience, this type of course sounds great in theory, but in practice can be an unsatisfying experience for students and professors.
There are many varieties of these courses. One in which I participated had a "theme" that was general enough to encompass a large-ish number of faculty in the department, but that was specific enough to make the course coherent. This also sounded good in theory, but the professor with primary responsibility for the class didn't do much to help keep the theme threaded through the course and the professors giving presentations were variable in the degree to which they paid attention to the theme. Student evaluations expressed discontent with the incoherence of the class.
In other classes of this sort, there is no attempt at a theme and the faculty who participate can talk about whatever aspect of their research they want. The purpose is to demonstrate the many different types of research being done in the department, and to introduce students, however briefly, to more faculty than they otherwise might encounter in their graduate studies.
I think that the success or failure of these courses depends not so much on whether there is a theme or even on how interesting the various professors are, but on the ability of the primary faculty member to provide context and to guide useful discussions before or after each presentation. Someone has to be in charge of these courses, given the high throughput of faculty in and out of the classroom during the term, and that primary professor has the responsibility of making the course as a whole comprehensible, e.g. by organizing supporting activities such as background reading, writing exercises, and/or discussions.
Does anyone like/dislike (1) being one of the professors who makes a brief appearance in these courses; (2) being the professor in charge of one of these courses; or (3) taking one of these courses as a student?
My department periodically discusses courses of this type, but the discussions are always inconclusive. At the moment, I am feeling somewhat cynical about these courses, not having had very good experiences with them to date, but I could be convinced of their worth by some compelling tales of life-changing experiences taking or teaching these courses. Or, to set the bar a bit lower, I could possibly be convinced by anecdotes of those who found it a moderately useful, even if variable, experience, to see a parade of professors describing their research field/expertise in one of these courses. [If you leave a comment about a student experience, it would be helpful if you indicated whether you took the course by choice or were required to do so.]