I'm pretty sure Silicon Valley is just getting started at walking all over this one, and the end results are going to be horrifying. Or maybe just annoying.
I never want something to brightly say "it looks like you're writing a letter", even if it's right. Even if the computer was smart enough to write the letter for me, better than I would have. Even if GMail has read a trillion emails and thinks it knows exactly what everyone's replies should be.
No, just shut up and let me write, let me work, let me live. No, I don't want to have a relationship with a machine. You be the tool; let me do the thinking.