I have only received 2 warnings.
1: Back when Moviebob reviewed Amazing Spiderman, I pointed out what a ridiculously terrible review it was, and that Bob might as well have not watched the damn movie for all the relevance his points had to the movie, since his opinion was based entirely on the fact that Bob was upset that they were rebooting the franchise. I may have been a touch too vitriolic, but no I don't regret it. It had to be said.
2: When the Sandy Hook shootings happened I made a post about how retarded American gun laws are, and that Gun advocates are idiots, complete with all caps. And you know what? I don't regret that one either.
So no. I regret nothing I've said on forums.