At the Ligonier Ministries 2010 National Conference (being streamed live here), Tim Challies spoke about Principles for Conduct in Communication.  He offered these tips to Christians who chose to use new and social media and other forms of online communication:

1. Be Visible - Don't seek anononimity online. Rather, allow others to see you and your activities.
2. Be Accountable - Invite a friend or your spouse to read your Facebook posts, blog posts, or even to search through your email account. 
3. Be Real - Don't pretend to be something or someone that you are not online.
4. Distrust Yourself

Solid words of advice to consider as I engage with others via email, Facebook, Twitter, and other means.