I was given a reference to an article on emerging trends over the next 50 years and it references on article on the trend of multiple identities in virtual communities.
I make a conscious effort to use a single ID on the internet to simply matters (yes, I am that lucky to have a unique first name!) - however, with the increasing trend of online collaboration and every person being just about my next door neighbor - this isn't scaling well from a practical standpoint and multiple identities and contexts naturally creep into play!
So I have a challenge there for those of you who feel bold - take identities currently being indexed on onXiam and mash each and every service to come up with one's master identity. We are not talking about universal logon of the past - we're talking about a very advanced, dynamic, and living data structure that is a representation of who you are. Thus, as more and more social sites are developed - this representation automatically becomes multifaceted in ways one cannot imagine and lead to exciting new discovery mechanisms!