It reminded me most of the science fiction short stories I read as a kid - rifling through my father's collection of best-of's from the 1960s. Take the real world, add an invention to it, and then see where it leads. That the invention doesn't have a clear explanation doesn't matter to me in the slightest - it's the story it's used to tell that counts, and I thoroughly enjoyed this one.
I can see why some people felt it was schmaltzy, but to me it was just a happy ending, and it fealy largely earned. Personally, I'd have gone to credits during the point where time froze - I thought that was a beautiful shot, and left things entirely open. Julie would have stopped when they were standing under the giant reflecting sculpture. But I can understand the writer's urge to make it clear that there's another version of Captain Stevens in the parallell universe he ends up in, who is still trapped, and leave us with an element of hope that that one might also some day get help.
Original post on Dreamwidth - there are comments there.