Miguel is absolutely correct. OpenACS is great technology but it remains an obscurest of platforms accessible only to the cognoscenti.
OpenACS and .LRN will not get traction unless the community pays attention to some basics:
* easy installer
* accurate documention for newbies
Caroline writes, "The person above felt there was no support, which is odd considering that there are commercial vendors."
Bizarre comment.
I can install Apache, MySQL, Moodle, Php. etc etc. in 5 minutes. The basic documentation is accurate and up-to-date. I don't have to rely on commercial vendors to get started with the system.