I always said I'd be the first in the family to get a microchip implanted, but my dog beated me!
Last trip to the veterinary he got a sub-cutaneous microchip with an RFID transmitter implanted. They just injected the thing on her neck.
Not much changes for stolen dogs, but the times of lost dogs changed for ever. No more signs posted on the corner columns and holding to a dog in the hope they will (or will not) come get it soon. Now, when you find a lost dog you can just carry them to the veterinarian's place and have them scanned, most probably they'll get an ID.
I'll guess I'll be next, just a matter of time ...
(I want mine with GPS and some other smart features though)