There is some very useful information here:
You are never going to win an argument with an online commenter. Most are not looking to engage in a meaningful dialogue. They are looking to take pot shots, to criticize and to not be held accountable for their comments. They are not anxious to look at another point of view, particularly yours, if you are the target of their animosity. Don’t waste time trying to convince them they are wrong and you are right. It’s like arguing with a slightly drunk relative at a family wedding who is yelling about one issue or another.
Could you imagine raising a contrary point of view in the middle of this family feud and your relative saying, “You know, Uncle Bob, that’s a great point. I never considered it. Maybe I should rethink my point of view.” It’s not going to happen at the family wedding and it’s not going to happen online.
Most anonymous commenters feel no need to check facts. Consider this personal experience: After numerous columns I’ve written for The Star-Ledger and NJ.com, I’ve seen many respond not debating a particular issue or point, but rather, to attack me personally or challenge my credentials. Some question whether I have a “real Ph.D.” One said, “Did you ever notice that Adubato never says where his doctorate comes from? He probably got it in the mail.” What am I supposed to say, that my doctorate came from Rutgers University in mass communication? Who cares? Plus, the author of that comment isn’t looking for the facts, he is looking to attack the messenger more than the message.
On the flip side, companies and individuals sometimes ignore a plethora of online comments that clearly communicate a groundswell of public opinion on a particular issue. When looking at commenters’ posts, it is important to note whether it is the same five or 10 people talking to each other totaling more than 100 comments or whether you have 100 comments from individuals. It’s not so much how many comments you get, but who they come from and what the specific themes and messages are.
I think there are some take aways from DU. Don't look at just recs. Look at the comments see how many are positive vs negative. The quantity and nature of the individual comments are far more accurate that the recs (that have been corrupted by freepers and sock puppets)
Another lesson is don't debate the hard corp anti-Obama people. Instead correct factual errors and offer up alternative opinion, but don't waste time in long debate as it is a waste of time.
As for the mood of DU and how it shows support for President Obama look at WHO is posting rather than just what is being posted. I have noticed the anti-Obama/anti-Dem stuff tends to be posted at least a half a dozen different times as the anti-Dems want to create illusions that their views are main stream (rather than the fringe 3% that polling has indicated).
http://www.nj.com/business/index.ssf/2010/03/lessons_learned_from_inside_th.html