multiple selves a fad or permanent change?

It seems to be pretty universally accepted that the vast majority of virtual community users, friendster members, instant messengers and so on are young people - either adolescents or not much older. This is reasonably significant in regard to how individuals form their identities, as these media allow much greater experimentation, as one's consciousness is not bounded by the mediating presences of one's physical appearance and physiology. What I wonder, is whether these media have been picked up by young people simply because they are young technologies - and today's youth have grown up with them as a given in everyday life; or whether they have become popular with young people predominantly because of the way they facilitate experimentation with identity, and a kind of practicing of 'real life'. Young people would surely feel this need much more, as most people reach a point in their lives when their identity becomes more fixed. As with most things of this sort, it is probably a mixture, but what will be interesting to see is whether today's youth let go of these technologies at some point and face 'real life' with a relatively unified identity, or whether they continue to experiment with their selves, remaining multifaceted and disparate.
Sam