You're allowed to change your vote... or comment more than once, for sure!
I just got off the phone with Cranston and they said that yes, this will be like "Wizard of Oz" in that they will be releasing more collections. Exactly how many collections isn't known yet, because it depends on how this one goes. But surely they need to include Melanie and Ashley, and no GWTW group would be complete without Mammy!