Bukkit

What is the enhancement in mind? How should it look and feel?
Restrict the copying of maps to the original maker of the map.
Like Bookworm, it would allow only the original maker of the product to hold control over its rarity (and thus the value) of maps, making them an actual commodity.
Roleplay server will love it, it will make map-making and intelligence gathering additional professions.

Please provide any additional information below.

I have NO idea how the Bookworm author is able to keep track of all induvidual books, their contents, and the copy-permissions, but

I will definitely look into this, although I don't think regular minecraft has a hook for the creation of maps I think spout does, although I have other ideas on how to do it for those without spout as well. (Like the first person to view the map would be the only one to be able to clone it, as it would probably be the player that made it) This would be an optional feature inside the config file.

Well, the Bookworm plugin manages to keep track of it all without the need of Spout. (it does use Spout for other cool features, but its not required) Maybe that dev is willing to lend some code, or pointers?