The reason for the move to LGPL is simply to make it easier when consulting.
Normally when accepting a fee for programming, the work is owned entirely by
the client. I have worked for a number of companies which required that the
work produced was co-owned by both them and the client, but this was always
a contentious issue.
The LGPL license sidesteps this nicely. Work done extending AgileWiki
plugins remains part of AgileWiki. Custom plugins developed for a client are
owned entirely by the client.