“How many networks can one person join? How many different identities can one person sanely manage? How many different tagging or photo-uploading or friending protocols can one person deal with?”
In his reply, O’Reilly remarks on the opacity of the network:
“When one of the big communications vendors (email, IM OR phone) gets this right, simply by instrumenting our communications so that the social network becomes visible (and under the control of the user), it seems to me that they could blow away a lot of the existing social network froth.”
Udell was focusing on getting social networks to critical mass, and O’Reilly was pointing the way to more usable applications. However, any solution will also have to deal with the attributes of digital artifacts that make them hard to deal with given our innate cognitive endowment. Scale and opacity are two; others include persistence, findability, and mutability.