Are you guys not using java's fullscreen exclusive mode? It should work almost exactly the same (at the application level, of course) on all systems.
Also, it's not OSX's fullscreen mode. OSX's fullscreen mode creates a new Space (a desktop in Mission Control); Minecraft's fullscreen mode does not.
The code change seems right. For the sake of consistency, I would make minecraft.toggleFullscreen() set the option value. Makes debugging just a little bit easier.
Otherwise, yes, this should be fixed very soon.