Whomever has me as a source but doesn't like the stuff I vote or submit regarding... hmmm... whatever topics are available, can now go to http://www.corank.com/editSource/RBA and make it happen.

This is the promised feature that allows you to discriminate your sources according to topics. It's available by going to My Account, Network tab, and where before you could only read "Remove" (to remove that person as a source), now you'll see Remove/Edit, and it's the Edit link the one that'll bring you to the page where you can check/unckeck whatever topics you care/don't care for that particular person.