A lot of companies today don't know what to do with social media. Some use it for marketing purposes while others fear it. It can be especially difficult for medium- and large-sized companies whose individual employees wish to blog, Tweet and post on Facebook on their own. Many people - from flight attendants to journalists - have lost their jobs because of their online presence, which begs the question: What is the appropriate way to express yourself online without damaging your company in any way? The problem is that the answer to this question is quite subjective, depending on who you ask.