Personally, I don't want every forum interaction I have to be a formalized debate, but that's really just my perspective and preference. Again, my preference:

Personally, I don't want every forum interaction I have to be a formalized debate, but that's really just my perspective and preference. Again, my preference: I come to forums for the side-tracks and interesting derailments, most of the time. It's sort of like going to wikipedia. Most of the time my enjoyment of the interaction isn't exactly about the topic, but in what other things interesting people bring to the table that I wouldn't have thought of. That said, I think there's definitely a place for debate-style forums, but I wonder how much that would be enforced by the tooling so much as by the tooling giving the user-base a lot of leverage and dynamic control in the way of enforcing the culture that is intended by the forum. In that space, I think a lot of these tools are trying to go down that path. Discourse has forking and branching for going off topic without derailing, and Vanilla has free form tagging that allows users to vote for things in a way that's consistent with user culture. I've never used vanilla, but I'm assuming you could also use the gamification aspect to promote users that interact in a way that's consistent with the interaction-style that the culture dictates, and maybe give them the ability to further or more staunchly enforce the culture (points/badges/whatever else for providing good sources, staying on topic, giving notably clear explanations, etc, etc). I also think that kind of thing gets difficult, and is as much about really being careful about outlining your expectations as anything, as well as adapting as there are new needs. I think of Stackoverflow when I'm talking about this, or on HN, where post titles will be changed sometimes, in a way that seems to adhere to the letter of the rules, but not the spirit, and sometimes seems to remove information that's relevant. My two cents anyway.