In a stunning example of what NOT to do, a man from a high-end PR company, on his way to making a presentation to FedEx in Memphis, put a comment on Twitter that was insulting to Memphis! That little Tweet got the attention of employees and executives at FedEx, AND the chain of command at his employer. Anyone want to guess how long it will be before this guy is looking for a new job? Yeah, I'd say about as long as his flight back to New York.
You can read all about it on Peter Shankman's site here: http://shankman.com/be-careful-what-you-post/.
Another tip - if you're in business and haven't yet signed up with Shankman's HARO (Help A Reporter Out), it can be worth the few minutes it takes three times a day to read his emails. HARO aggregates reporter queries seeking experts or people who can comment on topics for books, articles, blogs, and TV. He classifies the queries by subject area - some are from big names (Good Morning America, Huffington Post, etc.), and some are on short deadline. I scan the summary lines to see if there's anything interesting or that could apply to someone I know. A couple of times a week I'll see something that isn't for me but might be a good opportunity for a client or friend, and those I forward.
Is it worth the time? I think so. In December I was interviewed for a podcast series on women entrepreneurs that will run beginning this year. Even if you're not looking for publicity, it's a fascinating peek into the range of subjects that people write about. Sign up here: http://www.helpareporter.com/. Yes, it's free, and no, he doesn't spam.