No, it wasn't a joke, but I'm glad to hear that Mork is slated for death. I would've gone back to BDB myself, but nearly anything would be an improvement.

In any case, the point still stands that leveraging an existing project is often better than creating a new one... If not Mozilla::Mork, what would be the way to go?

Mail::Client::Yahoo doesn't seem to have any features to access the yahoo address book. Mail::Addressbook::Convert looks like it might be a good piece to work with... (The AddressBook module itself looks a little too simple to bother with).