|Image from Coloring Pages for Kids|
I joined Twitter on the 22nd of January, 2008, which means that I've had an account almost since it really took off in 2007, which has given me kind of a historical view of this issue.
I left the following comment on Rob's post today (with a few updates made):
In the early days of Twitter (when Guy Kawasaki actually wrote his own tweets), it was worthwhile to follow everyone that followed you because there wasn't anyone there who was not interested in tech and social media. It was easy to converse because you usually had common interests and time: minutes would go by without the twitter stream being updated with a new post. You had leisure to get to know one another and there was no such thing as a focused stream (except maybe for Scoble, who more or less left Twitter in May 2008). So it kind of became a custom to follow back those who followed you.
Much has changed since then.
Frankly, I don't understand people who follow back automatically anymore. Stephen Fry used to do this until his follower count got close to 100K (maybe he still does). I've got far fewer followers than he does, and I know I miss some of the posts I'd like to see (like those from Stephen). Can't imagine what Stephen's stream looks like and doubt he's even seen it in a while. Not to mention that all you have to do now is include a word like 'pilates' in a post and five 'bots for Pilates instructors will follow you immediately.
I read a quote that went something like, "other people's opinions of me are none of my business." Probably this won't work for a brand, but for just us folks, it works fine. You don't have to like me and you sure don't have to follow me on Twitter, even if I follow you. People who think otherwise are using Victorian etiquette in a rocket-ship world.