I too was a regular submitter to DD. I never had any problems getting listed quickly (for which I was very thankful!) but recently stopped getting approved e-mails. When I looked at the stats of my free sites that had been listed with DD for months, I saw that they'd all been pulled off his site. After freaking out, I went and read his updated rules (something I regrettably didn't do on a regular basis) and saw that he doesn't accept sites promoting a certain sponsor I used on most of my older sites and a few newer ones.
So, I've stopped promoting the sponsor (not just because of DD's rules but other issues as well) but fear I'm now on the blacklisted list.
