Credibility of Information

In reading all these posts and trying to get a better understanding of the role of libraries today and in the future I keep thinking about the credibility of the information source. Take for example the WolframAlpha Computational Knowlege Engine (http://www.wolframalpha.com/). I'm sure you've all seen it and used it with astonishing results. While intriguing, it's actually a little scary for me. It makes me wonder how the system works and how tools like this are reflective of the way we will mine for quick answers to complex questions in the age of wikis and search engines.