Permissions 3 introduces tracks and support for users to be in multiple groups.
Currently, /promote and /demote still work with the rank info tag. Could you possibly add support for promoting and demoting along a specific track (with something like /promote username worldname trackname), or add support for promotions/demotions directly to specified groups without the /user -setgroup permission, which currently allows users to promote themselves to groups with higher ranks than they currently have (e.g. a moderator could easily promote themselves to an admin with the setgroup permission, however I still need moderators to be able to add people to certain groups).