I love comparing written language to spoken language. Until very recently, written language was never "native" in the way spoken words are--they were used to record information, to share it over time, but not for casual spur-of-the-moment communication. Written language developed rules based on long-term archiving needs, not two-minute reaction needs.

And now we have written language that's serving the same purposes as spoken language: telling someone you'll be late for dinner, or pointing out something pretty that you won't remember in an hour, or asking who's available for a ride to the train station. And, heh, it's developing the same dialectic, slang-ridden, shortcut patterns that happen in speech.

I have some sympathy for teachers who have to push students into learning writing skills that directly contradict their social writing habits; I have none for people who bemoan the loss of the "purity" of the English language. English doesn't have any "purity" to protect.