Jeff Richardson and I will be speaking on this topic at the 2010 Federal Bar Association convention, which is here in New Orleans. If you attend our session (10:50 am at the Ritz Carlton), here are some up-to-the minute links on social networking that you may find useful. Of course, those who don't attend will find them just as useful so feel free to browse all you want!
P.S. If you want a better practice, check out this Ultimate Guide.
