Comment 3 for bug 164586

I have upgraded Rhythmbox to the Hardy version and tried what you described, but you seem to be mistaken. Rhythmbox _does_ support re-importing the same directory. If you import a directory and then later put a new music file there and re-import the directory, then the file is correctly added to your music library. The bug though, as I describe in my report, is that if you press Open immediately (i.e., the dialog comes up in the very directory that you want to import), then (for some directories) the button doesn't do anything and the dialog stays open.

No matter what the right design for the app is, leaving the dialog up without even showing an error message is definitely a bug.