I think it says something when I clicked on this thread I thought it was more likely to be an armchair imagineering thing than an actual rumour.
I really hope it gets this update, nothing they do will bring it to the Disneyland show simply because the Disneyland version isn't in an amphitheatre but it just happens on a lake that is magically transformed, but it'll be nice to see a new nighttime pull at the studios.
Of course, personally I would try to find a way to do a fireworks show in DHS again, simply because I hate the amphitheatre idea.