I think that one of the conditions to eminent domain must be that there is public utility. You cannot build a personal swimming pool on your neighbor's land, but maybe if the city decided it needed to put a public swimming pool there, and they could demonstrate that after duly considering alternative locations, that this was found to be the most suitable location, then I think they could very well eminent domain it.
I'm not sure if a private corporation willing to build a public swimming pool could do that. I guess not. I suppose transportation infrastructure constitutes a special case here. But I do believe that it only works because the railroad will provide a public service. If a private corporation wanted to build a private fun train to entertain its own managers and shareholders, but nobody else, then I don't think they could use eminent domain.