[southpawgirl]

Agree! Indeed, the comparaison with portals springs to the mind. While the amount of items (links, people, services, cultural niches) available increases, the need for more specialised and fragmented avenues of consumption increases. It's not difficult to imagine a scenario when one can pick and mix completely their online experience and still find their their social connections across different platforms, with the use of some meta tool, like an OpenId that also exposes the patterns of activities of one's friends.

As a purely empirical, nonrepresentative sample, I can see that most of my friends on Facebook are fairly quiet nowadays and my own account is virtually dead. It's still quite useful to have a FB a/c in order to authenticate on other apps; maybe FB will transforms itself into the aforementioned meta-tool...? Until it's superseded by a more specialised one...