What strikes me is that nothing has changed - people are still racking up the social networks (any one for FriendFeed?) and adding folks in a frenzy. Indeed, I would say since the article was written folks have been trying to get a grip on ring-fencing their networks, getting a handle on the purposes of different social networks, and trying to balance close ties and weak ties.
I'm not the only one saying that the brain evolved to handle large social networks and that social software should step out of the way and let the brain manage these connections. Indeed, Chris lists many ways that people manage large social networks outside of social networking software (go read about it).
Two things are bubbling in my head that relate to this.
1) We do maintain social networks by doing what social creatures like us do: meeting folks, writing, calling, and so on. The contact reinforces the bond. And our brains juggle all the level of relationship, the connections wearing a path in our synapses. What is the equivalent of wearing a path through our social network, without the software trying to be too smart (BASAAP)?
2) And speaking of paths worn down: I think this ties into what I think is the part of the next wave of the Web* - semantics. I've mentioned before that I am not into a priori addition of semantics in a librarian kinda way. I believe in our usage pattern establishing the semantics (heh, one of my triumphs of 'show vs. tell'). For example, the best way to decide where to put the paths on a commons (I'm from New England) is to wait a few months and see where the grass has been worn down. Another example, sort of, is when trying to understand tool needed during a repair, imagine painted hands marking every tool being picked up.
Ultimately social networking services -- be it LinkedIn, Tribe.Net, Orkut, or LiveJournal -- are making the problem worse, not solving it. Any engineer or information theorist can tell you that a system that only has amplifiers will be out of balance, and that you need attenuators in the system as well. Our current breed of social networking services have focused on amplifying our contacts not only because it serves us, but because it serves them. The more contacts that you make, the more people they potentially have in their service. However, in the long run this is unsustainable -- a social networking service also has to be useful -- merely amplifying your contacts isn't enough.
BONUS! If you think the Dunbar Number is bullocks, read this and this by Chris. He looked at the distribution of guild sizes in World of Warcraft and Ultima Online. Hm, what do you think was the average guild size? And under what size were most of the guilds? Eh, go read it yourself. The graphics say it all.
*Oh, and if you wonder what else I see as part of the next wave of the Web: machines as part of our 'social' network. See infovore for more.