I'm taking it. I've watched the introductory videos tonight. Tomorrow I will submit the assignments for peer review. I will also have an opportunity to assess fellow students as they will have of me. It should be interesting.
First main points:
Improvisation is like language. It has a vocabulary which is sounds (chords and scales). A grammar, which is a harmonic progression and your ability to follow it in a logical fashion. And finally, a there is the content. Namely your ability to develop a story, in sound, in real time.
Second main point:
Sounding like a jazz musician through memorising licks is similar to memorising French phrases and heading to Paris. You may sound temporarily like a Frenchman, but it won't take long before your inability to converse becomes obvious.
I look forward to taking this up tomorrow in class with my students.