When I look at my mydisneyexperience, it looks like I am able to select attractions, but I haven't gotten anything in the mail. Staying at AOA Sept 21-27 -
I logged on to My Disney Experience last night and was able to customize our magic bands and pick attractions for our Sept 15th trip to POP. We never got any notification from Disney that we were part of the testing, it was just a fluke that I logged on to check a reservation. I would say if MDE lets you customize, the go for it... We were even give a "bonus" FP+ our 1st night at MK, so we are scheduled for 4 FP+ that night!