I have extended the script to allow unmounting of the reader and memory card(s) together.
Code:
(*
Script for unmounting reappearing eBook reader volumes
writen for mobileread forums, © 2010 ischeriad
*)
set ListOfVolumeNames to {"STORY", "STORY SD"}
tell application "Finder"
repeat with VolumeName in ListOfVolumeNames
if (exists the disk VolumeName) then
set MountPoint to do shell script "diskutil info '" & VolumeName & "' | sed -n 's/.*Mount Point[^/]*//p'"
do shell script "dot_clean -n '" & MountPoint & "' && diskutil unmount '" & MountPoint & "'"
end if
end repeat
end tell