Like the swallows returning to Capistrano, or the prodigal son returning home to the family farm, my friend Scott Karp of Publishing 2.0 has decided to rejoin the Twitter-sphere. He stopped last fall sometime, and wrote a post about why he had decided it was a gigantic waste of time (one that made Anne Zelenka kind of mad). I wrote about Scott’s decision here, and said I understood, but that I personally get a lot out of Twitter.

In his post about why he has decided to rejoin the Twitterverse, Scott says that he has decided he needs to experiment with social media like Twitter — to eat his own dog food, as he puts it, since he is involved with a social media service called Publish 2 — and that he’s experimenting with a different approach this time in which he has reduced the number of people he follows on Twitter to 40, all of whom he “knows” in some sense.

My experience with Twitter — which I’ve written about here, among several other posts — is that it can be very different, depending on the person using it. There are some people I follow who never interact with me, and who I’m not even sure follow me back (meaning they get my Twitter messages). In some cases that’s fine, because they mostly broadcast thoughts or observations, and most of the time I’m OK with that.

Others I would like to correspond with, but they don’t follow me — which I find frustrating (and if you follow me and I don’t follow you back, I apologize for possibly creating the same feelings on your end). I can understand that for many of the people I follow, since they have hundreds and hundreds of people following them. How can they possibly interact with them all? And so what inevitably happens is tiers of relationships.

This reminds me of the “Dunbar number” — a theory that Robin Dunbar came up with, to describe what he thought was the maximum number of people that one could interact with on any kind of personal level. Dunbar figured the average was around 150. Some have claimed that they can boost that number online, and there’s no question that it’s easier to keep up a kind of intermittent attention flow with more people.

But does that produce any real value on either end? I wonder. Twitter seems to be riding that line, and it’s interesting to watch it develop.