I remember when I was always turning that feature off to avoid people getting irritated with me for not immediately responding because of the state of my queue...
To me it's not that awkward, I have no expectation that everyone else drop what they are doing and meet my needs immediately from a text/IM.
I regard these expectations as very self-centered. It really only takes a small short conversation and most people realize that it's self-centered to expect immediate responses to text/IM.
If someone needs my immediate attention I don't have a problem with them phoning me, or finding me in person. If they expect immediate attention from text/email/facebook then they are choosing to use the wrong communication medium.
Of course, the original post is only one paragraph longer than the boingboing excerpt.