My 2 cents worth (again).
Regarding Moodle – they already have a commercial venture (moodle.com) and a community (moodle.org), which WebCT never had. I think that it is unlikely that Moodle will start charging for its software, but given the nature of the license, the community could take the source code and fork it anyway. That’s the joy of the GPL. Yes, we should be vigilant but there are some safeguards built in to the community.
Also, I think that this post needs the link to the reference to Web 2.0 made in 1999 by Darcy DiNucci. O’Reilly and CMP were not the first by a long shot: