tobiasr - 10:33 am on May 7, 2010 (gmt 0)
We run a domain stats site where we got these as well because we showed stats on adult domains based on user input (like websiteoutlook). It looks like this alert is programatically triggered, not based on human review.
Actually we missed to act on the alert for three weeks and nothing happened in that time. Having said that I would strongly recommend as well to remove the content (we implemented filters) or not show ads on it.
It would be interesting to know what else triggers automatic alerts...