The system is similar to the SpeedPass issued by Mobil (the gas station) and uses RF technology to transmit the information. I've been very surprised to see it used in casinos, since I'm sure Gaming would have some issues with it (it's really not very secure).

You may continue to see it in new, smaller establishments, but not too many. Cost of the PT system is about the same, but those "bottle caps" are much more expensive than cards - and how many of you want a dozen of those things on your keychain?!?!