In Gentoo I had created a small script that was called by udev and allowed me to mount an USB device, identified by its serial number, to any mount point I chose.
SUBSYSTEM=="block", ACTION=="add", KERNEL=="sd[b-z]*", RUN+="/usr/local/bin/mountRemovableMedia.sh %k"
mountRemovableMedia.sh script uses the device parameter passed to determine the device serial, and then mount it to the mount point I want.
Now, in F21, with systemd, it doesn't work. The script is called (I have a log file written to by the script), the mount command is performed (returns 0, no error), but the actual mount doesn't happen: if I type 'mount' in a terminal, I can't see the device, and if I cd to its mountpoint the directory is empty.
I tried changing
udisksctl mount --block-device ... but it still doesn't work.