Even so, the plugin is very useful if your music collection is well organized in case of folder structure (by artist / album / genre or whatever). For example, if your music is not tagged or badly tagged, Rhythmbox won't be of too much help in finding the music you want to play but with FolderView, you should easily be able to find any track you want to listen to (of course, you need a decent folder structure for that). Another use for FolderView is when you don't remember a song name but you know the folder it's in or simply want to listen for some music in a certain directory.
Installation
Update: WebUpd8 reader zedtux has created a PPA for FolderView so you can install it in Ubuntu 9.10, 10.04 and 10.10 using the following commands:sudo add-apt-repository ppa:zedtux/rhythmbox-folderview
sudo apt-get update
sudo apt-get install rhythmbox-plugin-folderview
For manual installation (don't worry, you don't have to compile anything!) which works on any Ubuntu version or Linux distribution, do the following:
1. You'll need SVN to be able to download FolderView so install that first:
sudo apt-get install subversion
2. Then install the plugin:
mkdir -p ~/.gnome2/rhythmbox/plugins/ #in case it doesn't exists already
cd ~/.gnome2/rhythmbox/plugins/
svn checkout http://folderview.googlecode.com/svn/trunk/ folderview
Note: I've tested the plugin with Rhythmbox 0.13.1 only (on both Ubuntu 10.04 and 10.10)!
See also: Nautilus "Enqueue In Rhythmbox" Plugin Updated, Can Now Add Folders Recursively