I don't think we have chips in us (our bodies). What wouldn't be hard to do is stick one of them in your sneakers you just bought with your credit card at Foot Locker. These chips can not be destroyed by like microwave either. You would actually have to melt them. They're already putting these little guys on the things we buy. That's where we need to be looking, not in our right hands and forheads.
As for the issue of stealing that information... I agree, it would be very easy to "ping" the device and emulate a reader. Then you have all the information you need. If there are multiple layers to this information transaction then I would feel safer. A simple data trans like...
A>B Hey whats your number
B>A My number is ... xxxx
is creepy. If there was a way to setup an asymetric encryption channel, that would be preferrable.