All I know is that Rio Grande definitely has Union Pacific on it's most recent reprint schedule for 2007.
But we should put that in perspective. They had Wallenstein listed in the same way, even with the box cover of Wallenstein, but slowly over time it changed to Shogun. I expect the same in this case.
I'm both glad that I've got Union Pacific, and quite happy that I also have owned Wallenstein in the past so can see how much Shogun will be beneficial since it will be more accessible without having all of the german text on the cards.
It seems that Moon's Baltimore and Ohio might be something completely different from Union Pacific, and it seems he must have made enough cash from Ticket to Ride that he can stick to his guns and make his demands for the production actionable.