At the MIT Enterprise Forum tomorrow in Boston, I’ll be moderating a panel with three social software entrepeneurs on the topic of getting to critical mass. I want to ask the panelists about overcoming the friction involved in joining and learning to use their services.

Years ago at BYTE Magazine my friend Ben Smith, who was a Unix greybeard even then (now he’s a Unix whitebeard), made a memorable comment that’s always stuck with me. We were in the midst of evaluating a batch of LAN email products. “One of these days,” Ben said in, I think, 1991, “everyone’s going to look up from their little islands of LAN email and see this giant mothership hovering overhead called the Internet.”

Increasingly I’ve begun to feel the same way about the various social networks. 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?

Recently Gary McGraw echoed Ben Smith’s 1991 observation. “People keep asking me to join the LinkedIn network,” he said, “but I’m already part of a network, it’s called the Internet.”

Now of course LinkedIn offers protocols and features that the open Net doesn’t, at least not yet, and the same is true for all the specialized overlays that we call social networks. But there’s a ton of duplication in those layered protocols and features. If we can’t factor out a bunch of the duplication, I think social network fatigue becomes the major hurdle standing in the way of reaching critical mass.

I’m sure everyone will agree that sign-in protocols should be extracted and made common. What else can and should be refactored? What can’t and shouldn’t?