We do have a few publishers already on board including: http://digitalpayag.blogsome.com/, http://fslayouts.us.to/, and http://www.phonemyphone.com (if you count me :P). In addition, we've had an article written about us: http://www.howtotuts.com/2008/02/01/how-to-place-ads-in-the-...
We haven't really started marketing the product yet (that's tomorrow). I wanted to post to Hacker News before and get all of your feedback before the big marketing push (to work out any kinks in advance).
Other than that, good luck to you... I echo most of what already been said.
I have been noticing that I'm getting a request for Processing ApplicationController#index (for 153.XX.XX.XX at 2008-02-07 12:42:01) [GET] from some users which is causing the flash demo file not to be found.... but I'm not really sure how users can even get to that action since I don't have a method that defines index.
For me, that's what isn't working... the ad starts as visible, flickers on the mouse of whitespace, and stays visible after I move the cursor back into the demo. I see the default add as aligned top-left from the corner of the browser window: is that correct? (it covers your logo/title bar)
Also, do you have any publishers yet?