I think this will be a good program. The 1-800-Check-In program at Hyatt is great because you get your room number in advance. This makes it really easy to give your spouse or work your contact info.
I've also always had great success with the similiar program at Hyatt. You typically get the upgrade because the program follows the corporate standards, not what a desk clerk feels like that night
I'll look forward to the program rolling out in mass, and seeing what everyone's experience is.