Can PINs be assigned to playlists in 1.0?

Yes -- or at least, if they can't, that's a bug.

I'm inclined to change the PIN behaviour so that all songs with a given PIN get played when that PIN is selected; this is fine for the people who want that, and for those people who want their PINs to be unique, it gives them a quick and simple reminder that they've got a duplicate...

Peter