Who is first in your Social Network?

Some time ago in this post on Seth Godin's excellent blog he concluded :

Every person who encounters your organization for the first time comes with beginner's mind. She knows nothing about yesterday or how hard you worked or your financing or what it took to build it. She's here now, she's first, let's go.

That got to thinking about how true this is for our Social Networks too. When people join your social network (or the Societal Web in its widest sense) are they going to wade through all your previous posts or are the going to start from now. When a new person joins an individuals social network to them it is new - Your first message to them is the first message they have had. You are judged on what they see and not what others have seen over time. Sometimes we meet people for whom our experience seems at odds with other people, this is probably why. We need to be aware of 'newness' in relationships built through on-line social networks and recognise the need to adapt our messages and not assume that people know about what we have done before.  They don't.