Smarter part of social networking is get your employees for free ;D If you employ people and engage them in content management or info retrieval..it would end up being a costly affair. Instead allowing users to push in content is a smarter way to get traffic plus getting things for free. Now using a bot inside such a site would repeal traffic as they would view anything and everything as a bot. No one wants to talk to bots, they want to interact with a smarter being like them.