I'm signed up for almost every coursera MOOC.
I've only officially completed 1, and watched every video for about 30 others, and have downloaded videos 'to watch' for most of the others.
A few things I've found are that
1) Professors seem to like to assign waste of time busy work.
There are lots of classes that require essays or projects where it is essentially a giant waste of the students time. This includes doing videos and presentations for almost any course (a really well taught audio production course wanted every stuent to do a video essentially repeating a subset of the same material he just did. Others have wanted various large scale projects.) Since there would only be 'peer' evaluation of the material, this was all essentially busy work. There are areas where peer evaluation can be useful (some writing with rubrics and such), but mostly it was stuff that wouldn't matter at all from improving learning. Or the amount of learning improved versus the time invested was drastically out of proportion.
The math, science, programming and finance classes tend to 'get it right', only assigning an amount and type of assignment required to understand the material well, not wasting students time.
2) Science, Programming, Finance, Engineering, and Math courses are real courses, courses from Bschool and other sections are often ridiculously simple.
Of course testing and evaluating understanding of computer and science courses is quite easy, but still the quality and type of questions asked in reviews and homework and the type of assignments made sense for the Science/Tech classes; whereas I was sometimes wondering why the other courses had even bother to do a quiz the questions were so ridiculously simple minded.