That's what I heard and I heard it either here or on rebelscum. It seemed logical to me, but I never analyzed the scene to see if it was true.
It still looks like the hero to me though.
EDIT: I just watched the scene again. Its composed of 3 cuts. 1 cut of the saber shooting out of the snow, another of it flying through the air, and yet another of it in Luke's hand ignited.
It's not all 1 shot.
The may have used something to eject the saber from the snow, but while its in the air, there is no reason not to believe it was filmed as a throw and then reversed and composited with the other scenes. In fact, watching in in extremely slow motion, you can even see his wrist move backward as if he tossed it.