Hey guys, I run Zerk Media and we also happen to be working on something similar (http://adzerk.com). It will be interesting to see how they stack up when we both launch.
Hey James, glad to hear from you! Ad Zerk does sound similar, seems like we both had the same itch to scratch :) It is good to hear of another HN'er working on the same problem space. I am sure that our friendly competition will only lead to better products for the both of us.