An observation and two questions:

1) I believe you dismiss Moodle too quickly. You can set it up either by topic, chronologically, or as a set of forums. It was this last configuration that I used to create a community of practice for a Ohio state agency. So, Moodle doesn't have to follow the traditional course structure.

2) How do you define "course"?

3) What are the informal learning alternatives to the traditional course that you feel are better?