Even more common than fact checking on web is "incorrectly" fact checking. I don't know how many times I've read one fact on an article just to read another article that claims the opposite is true. Think about reading forums on Slashdot, how many times is a statement corrected, to then be corrected by someone else, to then be corrected, and so on ... which one is true?? Most of the time there's no citations! If there were citations, who actually checks them? From time to time I check citations only to find that the truth is being stretched, or downright reversed from the citation! It's hard to know where truth is, what's being exaggerated, what's only partially true, or more importantly, what's being left out. Everyone has a bias, and everyone manipulates data to prove that bias valid. The only way to get an unbiased opinion is to look at raw data, and very few people have time and ability for that.