The last Jenkins office hour of the year hosts Robert Sandell and Tomas Westling, who will go over newly open-sourced metadata plugin from Sony Mobile Communications (more about this story on their website). This team from Sony Mobile has been known for several other popular plugins, including the Gerrit trigger plugin. And I think this latest batch of plugins will not disappoint!
As I understand, this plugin is a library plugin, which is primarily meant to be consumed by other plugins. With help of other plugins using this plugin, it can classify jobs and slaves by adding metadata tags to them. This in turn enables more intelligent scheduling, views, access control, and so on.