com.stevestreza.iTunesBackup.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>Label</key>
	<string>com.stevestreza.iTunesBackup</string>
	<key>Nice</key>
	<integer>12</integer>
	<key>OnDemand</key>
	<true/>
	<key>ProgramArguments</key>
	<array>
		<string>/local/path/to/rsync-itunes.sh</string>
	</array>
	<key>StartCalendarInterval</key>
	<dict>
		<key>Hour</key>
		<integer>3</integer>
		<key>Minute</key>
		<integer>0</integer>
	</dict>
</dict>
</plist>

rsync-itunes.sh

#! /bin/sh

RSYNC=/usr/bin/rsync 
SSH=/usr/bin/ssh 
KEY=/local/path/to/.ssh/rsync-itunes 
RUSER=myuser
RHOST=myhost
RPORT=22  #I use a custom port for NAT-busting.
RPATH=/remote/path/to/iTunes
LPATH=/local/path/to/iTunes

TWEETNOTIFY=/path/to/tweetnotify

$RSYNC -qaEz -e " $SSH -i $KEY -p $RPORT" "$RUSER@$RHOST:$RPATH" $LPATH

# this checks the exit code of the rsync process
# if 0, assume success, otherwise assume failure
if [ $? -eq 0 ]; then
	$TWEETNOTIFY "iTunes music backup succeeded"
else
	$TWEETNOTIFY "ERROR: iTunes music backup FAILED"
fi

tweetnotify

#! /bin/bash

USERNAME="myusername"
PASSWORD="mypassword"

curl --basic --user $USERNAME:$PASSWORD --data status="$1" http://twitter.com/statuses/update.xml