Is Sending a One-Liner "Thank You" Email or Text Rude?

I've done it, and I suspect that many of us have done the same thing: sending one-word "thanks!" emails as a reply. But is it a rude thing to do?
Nick Bilton of the New York Times' Bit Blog asks whether sending a short email or text to say thank you is a rude gesture, as that essentially wastes the readers' time:

Don’t these people realize that they’re wasting your time?
Of course, some people might think me the rude one for not appreciating life’s little courtesies. But many social norms just don’t make sense to people drowning in digital communication.
Take the “thank you” message. Daniel Post Senning, a great-great-grandson of Emily Post and a co-author of the 18th edition of “Emily Post’s Etiquette,” asked: “At what point does appreciation and showing appreciation outweigh the cost?”
That said, he added, “it gives the impression that digital natives can’t be bothered to nurture relationships, and there’s balance to be found.”

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