I'm pretty much in agreement with what Marty said.
When the apps are complete, they would in theory allow your phone to emulate 2 remotes (presuming they can be run at the same time - I know pretty much nothing about smart phone apps) for the 2 different systems.
So for those in favor, they will be able to control both systems with one phone. If that works for people, I am not going to complain about it, but it's not something I'm interested in (I'm also on the fence about even the iPad apps that Lionel showed a preview of in October for Legacy)
I think there's a distinction there with the difference of having "one remote". That idea I think implies using one of the existing remotes to control multiple manufacturer's trains. For full functionality, that one is seemingly never going to happen.
-Dave