Who am I online? Personal identity construction on the web

How is one’s personal identity constructed these day? I’m asking, because I just read the announcement for a series of workshops and a special issue of the journal Minds and Machines on ‘The Construction of Personal Identities Online’.
Makes me think about how, over the last five or ten years, I have probably spent more and more time at the computer screen than face-to-face with my colleagues and staff here at the museum or talking with colleagues in seminars or at conferences. My sense of professional self — who I am, my identity as a professional, etc. — as well as other people’s sense of who I am has no doubt been formed, even to a considerable extent, through email and blogging and other online activities. (In contrast to my identity as a father, which I don’t believe has been much affected by my online activities.) Scary!