Kerry Miller - staff writer for Business Week, just wrote a great piece on the dos and don'ts of social conduct online. Her points outline the mistakes many people and businesses make when marketing with social networks. Online just like in the real world she says "is all about giving, not taking". Sometimes online users overlook that they are still interacting in a person to person format, I found a few points extremely relevent like these points below:
"Showing up in flip-flops at a white-tie event is no way to make a good impression."
"Collecting a thick stack of business cards may make you feel important, but it's not a very good way to glean useful contacts."
and "Establishing a new connection doesn't end when the party's over".
I'll disclose right now that it's an article about conduct on Myspace but I think it's fair to say these lessons apply elsewhere.