This is the only traditional forum I am still really active on. There's another from a podcast that is has started shutting down, so there's no point in including it. I've long dropped photography forums because of the trolling and vitriol. When someone with 50,000 posts starts telling others how things work, I have to ask how they would know - with 50k posts they can't have time to actually do it. <grin>
But, I do participate in Tweetchats, G+ groups and hangouts, LinkedIn groups, and Facebook groups.