I've seen a few merchants using a touch screen, including a few Gap stores in Montreal.

The requirements are that the consumer must have some way of concealing pin entry. That, and some stuff about how hitting different numbers can't make a different sound, or have easily picked-up electrical signatures, etc. I believe the EMV specs are publicly available, too.

Tamper-evident is likely baked into the device, instead. Make a circuit that trips when you open the thing up, wire that up to wipe the keys and brick the device until it goes back to factory.

Exactly what i was wondering. RBI (Reserve Bank of india) does not allow entering PIN's on touch screen. Infact they (RBI) go to such a length that a card processing terminal should be ONLY just the terminal and the hardware should be approved by the RBI which might take months.

Best Buy has PIN entry via touch screen

Pretty common here (New Zealand).