Topic Proposal: Incorrect information on Wiki sites

Wikipedia is one of my favorite places to search for information.  It has topics on everything imaginable.  However, the articles on Wikipedia are written by average people, and just about anyone can edit them.  Spamming and destroying articles with profanity and other graffiti are a big problem, but the biggest problem is incorrect information.  Every so often I come across information that contradicts other sources.  Wikipedia does a nice job removing information that is not referenced and making sure opinions are left out, but other wikis are not as apt about it.  This is a problem when searching the web for information, how do we know if the information is acceptable?