After seeing some of the gallery content, there is no question that the decision to pull the picture is made soley on the fact that it concerns male homosexuality. Tonymouse's violated no guideline, and in fact was more tame than some heterosexual and female homosexual pictures allowed to stay. This can easily be shown by analyzing gallery content, but judging from this thread, the point doesn't need additional proof.

Of course, Renderosity has the right to exclude artwork for any or no reason. It's just a shame that the moderators don't follow a consistent policy.