How do you deal with misinformation on social networks?

Do you think you should correct “friends” who post something as fact that is either a misinterpretation of the source they link to or a fabrication made up by someone else?

Some recent examples would be
» Stories about Obama firing Cattle Guards
» A post based on this story in the Daily Mail saying that since the arctic ice caps are 60% larger on a date than they were last year scientists are sensationalizing global warming and just “chasing dollars”. Also includes a misinterpretation of the statistics presented.

I’m not interested in arguing with folks, embarrassing anyone, or making people uncomfortable. These just seem different than opinions and seeing them presented and affirmed as fact bothers me I guess. Social networks are such a powerful medium because they come with an element of endorsement from whoever is posting.

Do incorrect facts bother you online? How have you (personally) decided to handle things like this? Does it matter who’s post it is? Does everyone need a soapbox no matter how wrong and should be left alone?