Automatically unsubscribe from legitimate emails like Gmail does?

There is a technology called Auto Unsubscribe that is supported by some email companies like MailChimp and others. Google now unsubscribes you when an email that supports this is marked as spam.

http://gmailblog.blogspot.com/2009/07/unsubscribing-made-easy.html

Is there a plugin for Apple Mail or could this maybe, perhaps, be added to a future SpamSieve release? This would help lessen the spam because a few of the emails might be from legit companies and the users, like me, might have forgotten they subscribed to the list.

Thanks for the suggestion. I’ll look into adding this to SpamSieve. The key is that it would be harmful to do this if the e-mail didn’t come from a legitimate company. Do you know of a list of good companies (besides MailChimp) that support this?