Be careful modifying stuff like that. There are logical volumes involved, which add a whole layer of confusion to the matter. Logical volumes show up in the system as /dev/VOLUMENAME/LOGICAL_PARTITION, so the fstab line is perfectly valid. It cannot be changed to anything less confusing.
To be honest, I don't know a whole lot about LVM simply because I don't use it. Whenever I format for linux, I just make real partitions. But here's what happens: The hard drive is formatted with one big "real" partition. Then LVM is setup in that partition, getting the /dev/VOLUME link instead of /dev/hda1 or whatever. Within this 'logical volume partition', 'logical volumes' are created. These are partitions, but are not seen by a normal partition manager. LVM is required to access them. Read here for more info:
To answer the original question, I have no idea how Gnome handles LVs (since I never use them), so I can't help you with the icon issue.
Edit: Also, it is
mounted as /storage right now. If it's not working, you may have to create the /storage directory. Just make sure it's empty.