My guess is that Disney is more likely to partner with Google on Android wearables functionality than Apple. It's quite probable that they do not trust Apple not to mess with the data collection functionality, because Apple literally opened up iOS to 3rd party open API development yesterday. (According to my Google search, the news release came out 22 hours ago.) As they still have a pretty solid monopoly, Apple could still choose to shut that door at any time, which could ostensibly orphan Disney's data. It will come eventually, but for now Android has the edge in that game because it is open-source.
I wouldn't write off Magic Bands too quickly. They have a lot of advantages in terms of throughput and uptake. There is no app to open, no battery life issue, no wifi connection issue, and they are easily replaced if damaged during strenuous activity, such as in the water parks or on an inverted roller coaster. There are situations where a simple RFID chip is the preferred solution, and this is one of them; it's cheap and durable, cannot be switched off, does not require frequent charge, and passively collects bushels and bushels of data. I suspect that while WDW won't give them away to every guest now, there will still be plenty of situations where "free" MBs will be tossed out as a premium.
