In late 2008, MailChimp Labs began Project Omnivore. Our goal was to build a massively scalable tool for our abuse team that could predict bad behavior -- pretty impressive stuff!!
We're seeing reports at OtherInbox of spam emails sent to email lists that are hosted at iContact. Our users give each website a different email address so it's easy to see when they get abused. I received an email with the subject "Pharmacy Best Product Vicodin.Viagra!!!!!" to an email address that was only given to Shoeboxed.com (a great service that I love).