Many applications choose to have a menu containing a list of recently used files, which can be used as an alternative to opening a file selector. GNOME, and KDE applications have done this for quite some time, and probably others have as well. This specification aims to do the following things:
Provide a standard mechanism for storing a list of recently used files (really, URIs)
Allow for notification of changes in the list
Accomplishing this will make using applications that are not native to the user's desktop a bit nicer, and give a more unified feel to the X desktop in general. It will be especially useful to applications that don't belong to a specific desktop at all, such as Mozilla and Open Office, since those applications could become compatible with all desktops in this area without special case considerations for each one.