It's practically gaming law that any title will never live up to the hype surrounding it. Games like Black & White, Blinx, The Thing, Time Crisis, etc.
The gimmick within the above titles never quite played out the way it was touted in previews and pre-release publicity. Whether I Am Alive's premise could be considered a 'gimmick' is up for grabs, I suppose. But I've been disappointed enough in the past to be a tad cynical.