According to the Filesystem Hierarchy Standard, certain directories/symlinks
need to be in /media depending on the available hardware.

From the standard (http://www.pathname.com/fhs/pub/fhs-2.3.html#MEDIAMOUNTPOINT):

"The following directories, or symbolic links to directories, must be in /media,
if the corresponding subsystem is installed:

Directory	Description
floppy	Floppy drive (optional)
cdrom	CD-ROM drive (optional)
cdrecorder	CD writer (optional)
zip	Zip drive (optional)

On systems where more than one device exists for mounting a certain type of
media, mount directories can be created by appending a digit to the name of
those available above starting with '0', but the unqualified name must also exist."

The section is not listed as optional, and while the '(optional)' after the
devices listed is slightly ambiguous, I think the only consistent interpretation
is that the devices themselves are optional, but the symlinks/directories are
not if those devices are available (note the "must" keyword in the first sentence).

This means that if HAL mounts a cdrom at /media/cdrom_label it must also provide
a /media/cdrom symlink to that.

I understand that using /media/cdrom is not the preffered way of doing things,
and that it can cause problems in certain situations, but I think it's important
to respect standards (various multi-cd installers break with the current hal
behaviour). If you would like to inform people of a better way of using cdrom
mount points (using HAL), then freedesktop.org should have a spec recommending
this (not sure if it does already).