Thanks for the replies, everyone.
We seem to have two basic ideas:
1. A Debian package, updatable with apt.
2. A GUI app that would manage all the different things and ways to
be updated.
The reason for the whole idea, IMO, is to make the process of
refreshing your wallpaper automatic. Over the years I've downloaded a
bunch of calendar-photo-type wallpapers, with a few non-photo, art-
style ones mixed in. Every so often I open up that directory and
choose a new one, and even less often I go to KDE-Look or Flickr, etc.
and download new ones. Sometimes I may go months with the same
wallpaper, while other times I might update it every few weeks. I
know that, for Windows users, there are things like WebShots that will
do it for you (though poorly, IMO; they tend to use low-res images and
add ugly text).
Well, back to the ideas, I like the idea of a Debian package, because
it would make the process for the user very simple: just set your
wallpaper to /usr/share/wallpapers/unique-name-for-the-autoupdate-
wallpaper.png, and after a normal system upgrade, you'll have a new
wallpaper automatically. Different packages could be chosen for
different themes, etc. KDE and GNOME can handle sizing down large
images for smaller screens, and a separate package would probably be
best for multi-monitor setups.
A GUI app is not a bad idea; it could present a more complex interface
where the user could browse by tags, choose how often to update, etc,
but it would be far more complex to make and maintain. Not a bad
project for PyKDE maybe (I am partial to KDE), but still much more
effort than a Debian package.
Any more thoughts? Maybe I should put this idea on w.d.o.