Disney spent a reported cool billion to implement the MyMagic+ system, which includes the Magic Band. Having just spent 9 days at WDW here are my comments on the new system.
On the plus side, the lines to get into the parks seem shorter. Disney has effectively doubled the number of places to scan your ticket or pass, and the process is quicker when it works right. There is still a finger scan which measures the length of a portion of your finger, and is apparently not a fingerprint reader. Sometimes the finger scan is thrown off by less than perfect placement or even hand lotion.
Many people had the Magic Band, and used it for park entry, Fastpass return, and even at the Sorcerers portals. You can get accessories for your magic band and even a t-shirt. The band makes it easy to spend money. Disney seems to be trying to make the band into something cool to have. However, using a room card kept in a protected wallet can be just as fast. When people go home from their trip they will be carrying the band in their luggage, or possibly still wearing it. The band can be scanned very easily, so people will have to rely on Disney knowing how to secure the database with account information.
When checking into a Disney resort, you assign yourself a pin number to authorize charges to your account. All well and good except that entering the pin on the pin pads in the stores, and at the resorts, is very visible. Anyone can see what you are entering because the pads are just sitting on the counter.
Another part of the new system lets people plan details of their trip months in advance. People can get Fastpasses for attractions long before arriving at the parks. This is probably good for people who like to plan out every detail in advance but, for others who like more spontaneity, it does not appeal at all. So, it would be like having an appointment at Haunted Mansion at 2:00 on the 10th. Probably not factored into the precise planning is the effect of bad weather, transportation delays, and big crowds. For first time visitors these are all unfamiliar situations.
The bigger picture is whether the $billion investment is going to pay off if essentially no new attractions are added. Right now, there is a feeling an watching an old plot with some new special effects. One would assume that Disney knows this and is hoping the MyMagic+ system will buy some time to create some different attractions before the novelty wears off. The wild card in all this is the potential for trouble with millions of scannable wrist bands floating around the world. Some have called this system a hackers delight, and Disney needs to be very careful to protect the personal information linked to these bands.
For now, the parks are very crowded and people are eager to spend money. There don't seem to be any slow periods anymore, thanks to Disney offering various deals and discounts.