Massive Open Online Courses

In recent years, MOOCs, or Massive Open Online Courses, have become more popular and common. These online courses can each have tens of thousands of students enrolled. Since summer, 190 universities have announced or launched 600 free online courses in a wide variety of fields of study. A list of these courses, along with links to other lists of MOOCs, can be found here:
https://medium.freecodecamp.org/190-universities-just-launched-600-free-online-courses-heres-the-full-list-3d9ad7895f57

Some things to consider:
What is your own familiarity or experience with MOOCs?
What are the pros and cons of these kinds of courses?
Many of these courses have free and open access. Is there anything in these courses (content, layouts, ideas, etc) that we could incorporate in our own courses?