The Quality of Forums in Online Courses

After reading George's comments about online communities, I got thinking about my coursework. I'm just finishing my fourth online course in a graduate program, and they've all had forums available, and all instructors assigned marks for using the forum. In fact, the bulk of the courses take place in the forums, which basically makes WebCT a very expensive message board.

What's interesting to me is that there's a huge difference in the quality and quantity of the discussions that take place between courses. Even though the tool is the same, the topics are similar, and there are the same number and type of participants...some forums just never thrive and people post the bare minimum to get by. In those courses, you never get into the subject matter in any real way. In others, there's rich discussion, with lengthy, meaningful threads that often don't stay entirely on topic at all, but still contain excellent learning.

So why are some forums (courses) more successful than others? Just like in F2F courses, the instructor sets the tone. In my limited experience, the successful instructors:

• select meaningful materials with the potential for controversy or emotional engagement
  
• set clear expectations for the type of interactions that are desired and acceptable
  
• participate in the discussions themselves as peers, but with the willingness to guide occasionally
  
• create clear, discreet sections to contain groups of threads...to make it easier to follow new ones
  

None of this would seem very difficult, but it's elusive for some instructors. I wonder how much help they get when setting up these courses?