I'll be the voice of dissent, and say that I don't like it.
If it had remained your roomkey card with your picture on it for verification, I'd be fine with it. But as it sounds like it is a seperate card, I now find myself keeping track of 3 documents when going to the park (park ticket, roomkey and now the express ticket). I'd prefer all three to be combined into one card.
Also, how would these kiosks work? Slide your roomkey for verification, have your picture taken, and then a new express pass gets issued. As it sounds like these can be reissued, what happens to the previous pass if a new one is created? Does it get deactivated? I would hope so. Almost seems like there's an increased chance of fraud if people can issue multiple express passes with one hotel keycard.