Okay, I just got back from the World. No trip report, but I did make some observations relevant to topics discussed on this thread, and I'd like to sprinkle them in here as I get a chance.
First up, RFID cards. No issues using them as room keys, but so insignificantly better than sliding a card as to be mostly irrelevant.
It was confusing using them to get into the parks the first few times, and most people had to have their hands held by the CMs at the entrances, really slowing things up. And even for people who were familiar with using them, they were still no faster than the old way, and probably slower. There is a perceptible delay between tapping and the "spinning" starting, and then you still have to wait a moment to use the biometric reader.
But the real issue came with using them for purchases. My card was recognized/authorized by tapping less than half the times I tried to use it. This meant swiping or entering the card manually. And having to enter a PIN for each transaction was cumbersome and time consuming, so I don't see where the supposed efficiency is going to come from.
And now for an opinion. Anyone (like the execs behind this) who thinks the Magic Bands are going to lead to a lot more impulse purchases is either delusional or never actually steps foot in the parks like a guest. I keep seeing things like "see something you want, and then just tap the band and go". Problem with that is there is almost NEVER a time when there is no line at checkout for purchasing anything, anywhere at Disney World. So where does that impulse, with no time for second thoughts, come into play again? Even if the bands do make checkout a bit faster (which I contend is unlikely thanks to the PINs), does anyone really think there will be cash registers without lines- anywhere or at any time. And call me old-fashioned, but making the effort to pull out a credit card or other payment is hardly a chore that slows me down, it's what I do naturally while waiting in that (usually long) line to checkout.