All that is published for Identity platinums is "complimentary room upgrades". I went from an Identity nobody to a platinum on one stay, so don't have any personal experience yet to say whether the benefit is one or two categories, or more. Stories posted here (in this thread) show Marriott platinums getting some pretty good upgrades, for instance a base room to a wraparound suite (undoubtedly when occupancy is fairly low). I guess the best of all worlds is to be platinum in both programs, and hope they recognize double-platinum status!
