Twitter: Social Networking Tool or Credible Journalism?

I believe that Twitter is a social networking tool, period. Twitter is not a credible journalism source. If Twitter is going to be considered a credible journalism source, then Facebook and Myspace should be as well. While we're at it, why don't we make Wikipedia a credible source as well? The reason why is that anyone who has access to the Internet can post anything on Wikipedia, they do not have to do any research or even be a credible source. The same goes for Twitter as both also fail to be unbiased as they are the thoughts & words of an individual.