When I first started using Google+, I had a sense of déjà vu as I categorized my friends. I’d done this before… on Flickr, on Facebook, on Twitter, on my instant messenger contact list, and in my address book. Shortly thereafter, I came to the conclusion that it wasn’t worth the effort to rigorously group everyone. Then I started thinking about whether it was ever worth the effort to do so...[T]here are some human subtleties we’re missing in the digital world.
Fascinating analysis of the necessity of putting friends into groups, and in particular, Google+'s cool Circles feature: