on self-presentation online

An acquaintance's blog post on the ambient intimacy available online via, e.g., Twitter reminds me of something I wrote in 2002 on my weblog, which still obtains:

I'm not my whole self here. If you are your whole self in your weblog, if I could completely know you by just reading your weblog, then you've broken some barrier and become a Philip K. Dick character, or you have a very small life.