You work very much at your own speed and can do as much as you want each week. The week is usually divided up into sections and after each section there is a chance to join in the online discussion with other course participants, but it is entirely up to you whether or not you do this.
The course contains a mixture of pieces to read, a tutor talking or a video and there are often links to other sources if you want to follow things up. I think there are also quizzes after some of the sections, but you get lots of chances to get the right answer.
There is no pressure at all, and if you decide you want to miss out sections or even give up completely no one chases you up.
You can chose to follow people on there, so that when they comment you can see what they put - it's quite a good idea to follow the tutors. I know that when a lot of Rootschatters did the genealogy course a year or so ago, we made ourselves known and followed each other.
Hope you enjoy it.