For those of us who create many temporary databases that get deleted, the new functionality that leaves database directories intact (even when they're not mount points or symlinks), can cause problems of managing the server.
Please add in a flag or set of options (json?) to allow us to tell dropDatabase to delete the directory upon completion. This would act the exact same way that MMAP does today.
Additionally, you could provide the option to delete "only if not symlink or mount point" or any combination of those options.