I finally had some time to re-organize the SVN repo and create a rails installer. Here’s the install command / path:

ruby script/plugin install svn://rubyforge.org/var/svn/rubyamf/tags/current/rubyamf

The new repo is laid out with the suggested standard directories.

/trunk -> development
/tags -> previous revisions. Always defined like: rubyamf_{version}_{revision}
/tags/current/rubyamf -> rails installer directory

Also; thanks to Simeon Bateman for a quick tip on re-arranging the SVN for some better organization, tags for previous version, and the rails installer.