The instructor should always participate in this assignment so that the students get the sense that the instructor is a part of the class and is a real person.
I feel that this is a very important point and can be applied to other Online learning situations. It is very important for an instructor to show they are invested in students learning and are a "real" person. Many instructors have commented to me that they feel their students don't realize that they are more than the label of "professor". They have their own lives and opinions.