Later on in the development of 1.5 we create a general media folder to all assets. At the moment this folder only holds the none-BC system assets. The idea was that the installer would push component specific assets in this folder during the installation process.
In JInstaller around line 780 we see the following in the parseMedia() method:
/* * Here we set the folder we are going to copy the files to. * Default 'media' Files are copied to the JPATH_BASE/images folder */ $folder = ($element->attributes('destination')) ? DS.$element->attributes('destination') : null; $destination = JPath::clean(JPATH_ROOT.DS.'media'.$folder);
Doing it this way gives us the ability to start taking all of the media assets out of our code folders and get us to a point where we could really move all the PHP files underneath the document root. It is a first step toward that end.
For the original discussion, see Joomla! Developer Discussion List.