Custom icon support added and configurable per-dial stored in a JSON key:value pair in localStorage is all good to go if you'd like it.
Since it can be the basis for actual thumbnail support sometime using base64 encoded CSS background URL's instead of using immedianet. If we can store any URL with any thumbnail as base64 encoded data we can store and use our own thumbnails locally sometime but I'm quite happy as it is from my additions to lay the groundwork for now.

It was the img tag that caused the limitation for custom icons/thumbnails since images/backgrounds is CSS territory now and img tags are images of the past :P
It's also strict mode compatible now :)

http://www.iconarchive.com/ is a GREAT place to grab icons from too, so maybe reference it for people to find really amazing icons that suit them perfectly if you like.