Have to say the above members are spot on with their posts.
I can tell you from experience also with assisting other sites, not to worry about it. In the end it will all come out who is being the real brat..and well it just isn't going to look good for that person exhibiting that type of behavior.
Members do not like to get into "wars" of business between other sites. They come to these sites to have fun and get away. Advertisers do not like to see sites that engage in this type of behavior either. This person, if advertising, will soon learn the advertisers will not tolerate it when they pull their ads from their site.
It may take some time to settle down. But I also suggest ignoring it,

.