1. Social media use has grown rapidly, with three out of four U.S. adults now using social technologies and tools to connect and share information. 2. Popular social media sites serve different purposes - Facebook and MySpace focus on personal lives, LinkedIn is for professional networking, and Twitter is for opinions, news, and chat. 3. Marketers need to engage where members and customers are congregating online rather than using traditional static websites, and be prepared to respond honestly to feedback to avoid a lack of authenticity.