How often do you visit other answers sites like Live Q&A, Askville, Dictionary.com, Answers.com, Wikipedia?
I go to Wikipedia when I want to find out something quickly, but I don’t consider it similar to Answers. I don’t think I’ve ever even looked at those others you mention. Perhaps it’s loyalty, since Answers gave me an award for “Community Leadership” at their birthday party last December. They sent a chauffeured car for me and my guest, wined me and dined me and put me up in a nice hotel with 23 other awardees. They get some major points for that, but also I got to meet those other 23 people, and have a good time doing a community service project with them, and discovered I had some very cool friends in Answers.