Nick Bilton writes about contemporary etiquette for the New York Times blog Bits:

Some people are so rude. Really, who sends an e-mail or text message that just says “Thank you”? Who leaves a voice mail message when you don’t answer, rather than texting you? Who asks for a fact easily found on Google?

Interesting read, particularly when it comes to e-mail — I think the issue is related to the ways employment is linked to e-mail.  The inbox suddenly becomes a task list, not a mailbox.