Lol.. I have an 18" flat screen in my trunk. And it actually does scale pretty well up to that. Depends on what it was "DesignedAt". It it's designed for 640x480, it's not so hot w/ the larger size, due to pixels being "stretched" to cover the space. Though if ALL skins were designed at say "1024x", there would'nt be any problems. Things scale down ALOT better than they scale up.
So maybe that should be the way it's done. I dunno. I have a few ghetto skins done now just to test things out, and so far it does seem to work pretty well. I'm using jpg images, and creating masks internally to have them "appear" transparent.