I have not yet seen "Her", but this strongly reminded me of Ender's communication with Jane from the "Ender's Game" sequels. One of the most interesting facets to their conversations is that Ender could make sub-vocal noises in order to convey his points—short clicks of his teeth and movements of his tongue—that Jane could pick up on but humans around him could not. It is the "keyboard shortcuts" of oral communication.

If "Her" is really the future to HCI, then sub-vocal communication is a definite installment as well.