Fun project!
I was poking around and notice that the extension needs to be updated to get new shows. Is that desired behavior--I'm guessing you'd prefer new shows to be downloaded more seamlessly. If there's a bandwidth issue (i.e., the downloads are done via extension updates to put the bandwidth on Mozilla's servers) then the new art could be made available via Flickr.com and then periodically downloaded by the extension to be stored locally.
Actually, as I type this it occurs to me that perhaps the art images could simply be kept on Flickr and not stored locally in the extension folder. I'm thinking that after the first time the images are downloaded they'll be in the users' browser cache and won't have a performance hit (or delay for displaying).
Anyway, if moving away from updating the images via extension updates sounds interesting, I'd be happy to join the development effort and make that happen.
