I had a pretty good one in grad school--well, it was a hybrid, where we met once a month in class. I've also taken some pretty bad ones when I took some random undergrad stuff like 10 years ago. It does depend so much on the professor. And the other students, in terms of discussions.

One of my freelance gigs is actually editing online college courses, though I have nothing to do with their administration. They generally include discussions, with requirements for interacting with other students. Some of them can be quite dry as well...I just finished one for School Counselors that was pretty interesting though!