I have some technical objections.
First and foremost, from the FCC documentation released so far regarding radios, the only, ONLY antenna in the device is for the 2.4GHz data spectrum, not GPS (2.4GHz = WiFi. Makes sense now, no?) There simply isn't GPS, from what has been released so far, in the device. In fact, a GPS system inside the device would require FCC disclosure, further testing, and a much larger device. I simply cannot believe that there is a GPS device inside the unit that is tracking our movements.
Now, GPS LIKE, where the use of WiFi signals and towers can triangulate a location, that's another story, and one that is significantly less accurate in it's locating services.
The wristband is simply a WiFi chip that broadcasts a set of data to a terminal. This is an active RFID system, not passive as many have thought it would be. An active system would allow for a MUCH more secure system, but still not un-hackable. The idea of hundreds of thousands of techno-idiots walking around Orlando with their personal, financial, and other information attached to their wrists is a dream for thefts.
I don't see how Disney can force anyone to give any information beyond a name for these tags. I have had Resort IDs given to me with other people's names on them because CM's don't care and/or other shady reasons. This NextGen service requires that CM's stick to the rules all the time, guests always wear these, and there is no infrastructure weaknesses (ha!). Right now it SEEMS that the only testing has been for the passive RFID in the form of FP+ cards. Any well designed system can handle this as the technology has been around for years if not decades (see wireless pay on credit cards.) But I don't think there has been a system deployed, ANYWHERE, where 40,000+ roaming, active signals over 300 acres is tracked on the level as described by '74s sources. Again, this is my understanding, and if someone can correct me I'm all ears (no pun intended).
Again, this is my observations based on my exposure to technology, the patent applications, the installed infrastructure, and so forth and so on.