You're talking about Islamic forums in English, right? Because the most successful Arabic Islamic forums out there are controlled by Salafis. I think Sunniforum is succesful because there aren't many Islamic forums in English on the web in the first place. And what do you mean there are balanced views and respect for ikhtiliaf madhabi in this forum? If there is any thread that is threatening any ruling of one of the four madhhabs, they simply delete it, or make it inaccessible or uneditable (like it happened to my thread). And "many knowledgeable people"? When I want to ask difficult questions I have to ask them in Arabic forums.