It seems many people are struggling with how to classify different contacts in the social networking services you use: is your boss your "friend" on Orkut, and are your drinking buddies valid LinkedIn contacts?

To make things easy, let me introduce the beer rule:

• User needs two social networking services. I use FaceBook to keep in touch with friends, and LinkedIn with business contacts
• If you can contact somebody at any time and go for a beer: personal contact, ending up in FaceBook
• If money is involved: professional contact, ending up in LinkedIn

Simple!