Using Elisa I've noticed that when it presents the playable files, it simply shows the way they are in the file system. As it turns out, my folders have pretty ugly names as there are albums that I've downloaded off the Internet. My pictures are also quite disorganized in the file system. I'd be nice to support Banshee's and F-Spot's database (if available) and show the data that they contain instead of a plain file browser. In my personal case, my music in pretty well organized inside Banshee, it "abstracts" me from my file system structure and it is obviously way easier to find data inside Banshee's DB than it is to find it through a simple search tool or Nautilus for instance.
Banshee and F-Spot could also be promoted as Suggested packages to install.
AFAIK Banshee parse id3 and other metadata of your audio medias... Elisa can do the same and you can browse your music by artist/album using a plugin called meta_fs. You just need to enable the media_manager in your ~/.elisa/elisa.conf file, just like this:
[media_manager]
enable_cache = 1
We already thought about reusing other software databases, but it would be far more interesting to design a Desktop agnostic database schema that all software could use. Metadata parsing is supported by Beagle and Tracker, but these are (AFAIK) Linux-only solutions. Here we do our best to design a cross-platform mediacenter application, so this problem is not trivial to solve.