I would love to see something like this, only with two additions:

1) A small LCD display
2) A hardware button

The reason being (and correct me if I'm wrong here), with the current model you have to trust the POS terminal to request payment for the same amount that its display shows. What if a POS terminal is hacked / modified to request larger payments than the display shows? Or what if malicious persons set up secret hotspot terminals to steal bitcoin from accidental proximity?

What I'd like to see is a two-pass system: one wave "receives" transaction data from the terminal, and displays the requested payment amount on the LCD screen suggested in point 1. If you'd like to confirm the payment, you simply press the button mentioned in point 2 and a second wave will "send".