I agree that ignoring abusive posts is probably the best way to deal with them. Personal messages are also probably the best way to show support, as they accomplish your purpose without adding fuel to the fire. This is the way I have tried to respond to these incidents, and the way I will continue to respond. I don't post to a lot of music threads because I don't always have anything to offer, but I read almost all of them and learn an awful lot by doing so. As to those who must try to disrupt things here, ignore them and they'll go poop in somebody else's sandbox. Just my 2 cents worth.

jeffp