The meaning of a portrait is entirely dependent on the social, cultural, and historical context of its creation (the artist), commission (sitter), and viewing (audience). If one were to glean anything from Brilliant's writings on portraiture perhaps it would be that identity is a fabrication of A) the "artist's imagination", B) "desire and role of the subject", and C) the social context of the portraits presentation to society.
Portraiture in this way is a framework for defining the relationship between the self & the world. It is about capturing an aspect of the nature of identity, and re-presenting for a social purpose. We present and represent the self as Art, Biographical Documentation, Historical Information, Personal Memorabilia, Political Iconography, Memorial Imagery, the list goes on.
In light of the multitude of roles it can play, from the empty images of Marolyn Monroe to the iconic & stoic portrait of Weber, how will the tools and context of the information age transform portraiture? Will portraits still try to capture a "timeless" self, unique and yet comfortably portrayed in the generic type roles of their day? Does interactive portraiture allow for a more "authentic" view of identity?
Oscar Wilde said that Portraiture is really a portrait of the artist (p. 82). Jon Gerrard attempts in his works to overcome the subjectivity of representation by presenting super-high resolution images of his subjects in three dimensional views with Matrix like 360 degree rotation. The viewer can change the angle of viewing by rotating the video image along an arc in the gallery.
The feeling I got in the gallery was of a sort of hyper reality, where the iconic role of the subject is lost and the sense of a likeness dissolves into a clinical view where one sees many more details than you might in your everyday perception of the same person. We see people in different lights in our everyday lives and as locomotive creatures have a holistic representation of their form, but we don't often flatten this perception into a massive quantity of data and present it in such a surreal way.
Gerrard and Bill Viola both use portraiture in this way to evoke how the role of technology can amplify our experience of portraits by slowing down time and increasing detail - somehow our iconic representations of each other are lost and we move beyond our idea of identity. Shearer West said that portraiture is about body and soul - these portraits seem to leave the soul behind the facade of the exquisite copse.
I have also been living and working with a portrait series by Orit Zuckerman called Influence. I'm sure everyone at the Media Lab is familiar with it - to me it is the most authentic representation of people in a social context that I have ever seen. Influence is an interactive artwork visualizing how collective behavior emerges from decentralized interaction in a small social network. Individual people are affected by the behavior of people around them, and as a result, they influence the people around them as well. As I have lived with it I have come to appreciate how accurately and sensitively Orit and Sajid approached their subjects - and how considerate they were about how the subjects were presented. A remote control interface allows a viewer to explore the personalities and reactions of each viewer.
So in each of these examples I would say that yes, they function as portraits - but not in the same gnomic way of the past - instead they posit new technological and social contexts for viewing a person and place the act of portraiture into the role of observing itself. (as Escher did but by placing himself in the eye of the viewer).