In a thought-provoking post, Sustainable Life Media blogger John Friedman writes about the importance of your social media presence and how each of us is judged — for better or for worse — by the tweets, posts and photos we choose to share online. "A few choice words can define you," Friedman says, and reminds us how easily information — positive or negative — can be shared these days. And how difficult it is to take back something you share online but later regret.