I've created some simple wiki pages on how the dependency
system "hangs together".
http://wiki.jboss.org/wiki/Wiki.jsp?page=JBossDependency
This definitely needs fleshing out, especially with a better overview. :-)
It also contains the start of an explanation on how the integration works
to replace the old MicroKernel.
http://wiki.jboss.org/wiki/Wiki.jsp?page=ServiceControllerContext