I've published a new version of the framework core. As with the previous versions, the PluginManager is now included in the core download (even though it's a separate project with its own SVN repository). The newest version adds a few very minor feature enhancements. The largest change is the removal of the Scriptaculous library, which has been replaced with a jQuery plugin in the PluginManager source directory. Also, the PluginManager index page now scans for and automatically expands new zip archives in the source directory.
See the release notes for additional feature info.