Received an email a few weeks ago that they were going to stop the parking revenue feature due to click fraud. It may have started May1.
Here's the email they sent
Dear John,
Starting May 1, 2010, we will no longer be offering our Dynadot Revenue Parking service. Any domains set to Dynadot Revenue Parking will still show the same parking page, but you won't receive account credit for ad clicks. This change is due to ongoing issues with click fraud, and it affects all accounts using Dynadot Revenue Parking. We will continue to credit the previous months parking revenue up to April 2010.
Best Regards,
Dynadot Staff