X-FOAF in Mail.app

Ok, here are the usual references: The idea and the mac-related implementation. But what’s next? A fancy plugin for Mail.app to open up [foaf-explorer][3] or rules that highlight all mails from people with X-FOAF headers? Or maybe a plugin that tries to pick up the gpg keys of people to grow my gpg keyring automatically to fully encrypt the next mail to the sender which just got in my mailbox with an X-FOAF: ?

[3]: http://xml.mfd-consult.dk/foaf/explorer/