It would be very interesting to be able to use an URL in the icon parameter and fetch it asynchronously without slowing down the Feedback.
Today we need to fetch/save the images and this considerably slowing the process because it's synchronous. Something like this would be neat:
<?xml version="1.0"?>
<items>
<item uid="rdioartist" arg="r96664" valid="yes" autocomplete="Incubus">
<title>Incubus</title>
<subtitle>Artist</subtitle>
<icon type="url">http://blablabla.com/rdio-artist.png</icon>
</item>
</items>