Batch or BFX is actually the difference between Smoke OSX and Smoke Advanced on Linux. There is even a greater difference between Flame. Which has more bells and whistles. Like 3D tracker and substance textures, particles, projectors, etc.
There is also a Flame premium license which unlock all of those wonderful toys in Smoke Advanced.
Flame Premium also gives you Lustre, Autodesk color grading app.
Personally I don't think there is that much difference between the capabilities of Flame and Smoke Advanced. Like Brian said, you get some extra features mainly. The big difference is the interface. I much prefer the Smoke editing based interface.