Was there ever any doubt? Well, maybe. Heh. :P
Read the whole article & see the list of shows: http://tvovermind.zap2it.com/tv-news/survey-results-show-strongest-online-fandom/54237
"Supernatural fans also are more active in the qualifiers for 'fandom'. They do not just watch the shows, they interact. More than 80% of Supernatural fans have started new social networking activities because of the show, compared to only 60% of the fans of other shows. 75% of Supernatural fans have produced creative enterprise (fanfic, fanvids, fanart, etc) inspired by the show compared to only 58% of fans of other shows. Supernatural fans are also prolific. Fanfiction.net has more than 47,000 works for Supernatural. Castle, the show with the second most passionate fandom in our survey has only 3,500. Supernatural fans also vote. For anything. Often. 98% of Supernatural fans say they vote in polls, compared to 91% of other fans. 70% stating they always vote, with 45% voting more than 50 times per poll. In comparison, only 56% of fans of other shows claim they always vote, and only 30% vote more than 50 times per poll. Finally, 30% of Supernatural fans have attended a convention for their show compared to only 12% from other shows."