These maps are pretty quickly caught by the developers and removed. And if not, they tend to be downvoted, which takes them out of the rotation pretty quickly. You can also contact them yourself to report inappropriate content. A very quick Google search led me to their contact page here.
But keep in mind that, with the way the game is set up, you're going to have inappropriate usernames, language and, occasionally, maps. Online interactions like this simply can't be monitored effectively, and is certainly outside the purview of our staff and moderation team.
While I haven't played it in the last few days, I have played it regularly for a while, and just did a few quick-matches right now. I don't appear to get the same maps as you do, apparently. Yes, I've seen several user designs on the balls that were not OK, but the levels have always been fine, in my experience. And they do change regularly.
And votes on maps don't help because people easily manipulate those results.
How could you tell that?
It is your choice if you think large images of genitalia posted as the front page of a game for 12 hours (an entire day) is not in your purview.
I think Moe just said that it isn't, no :-) You'll have to contact the game developers, really.
