Comment 1 for bug 145256

Yep, we could study the protocol that uses iChat wich is not based in PEP/Pubsub and write a component compatible with it too. Presence and iTunes: XEP-0118: User Tune. iChat uses this (correction: announces the xmlns http://jabber.org/protocol /tune but doesn't, see below) to tell the other peer which iTunes music are your listening. When you play a music on iTunes, iChat sends this presence packet to the server (and the server will broadcast it to all your roster friends). The packet includes the artist name, the song name and the iTMS link for your to buy the music (if available). Very clever stuff.

    <presence <email address hidden>/iChat' <email address hidden>'>
        <status>Driving On 9 - The Breeders</status>
 <priority>0</priority>
        <x xmlns='vcard-temp:x:update'/>
 <c ext='avcap avavail maudio audio' node='apple:ichat:caps'
     ver='388' xmlns='http://jabber.org/protocol/caps'/>
 <x xmlns='http://jabber.org/protocol/tune'>
     <title>Driving On 9</title>
     <x xmlns='jabber:x:oob'>
    <url>itms://itunes.com/album?p=27552046&i=27552037</url>
     </x>
     <artist>The Breeders</artist>
     <source>Last Splash</source>
 </x>
    </presence>

This info from: http://celso.arrifana.org/?p=6