We simply haven't heard from them, right. It's not like they told us they wouldn't renew the contract. I think it's just a matter of poor/busy J-list staff.

I would doubt they check each individual site unless they already suspect something due to repeat winners (which I suppose could be the case here). Most likely they normally judge by ad traffic which I think we have a fair amount of. At the very least, I remember hearing we were getting a lot of traffic on those unpleasant ads we had up for a short time.