OK, so Hyperspace is telling you how they are filming the climactic duel these days. An insider we'll call Leak from now on tells TFN something very interesting about one of the guys in the film - and in that sequence:
Early on us members were told that we would help visualize Anakin progressing to how we know him from the Classic Trilogy. By that I understood he would be closely resemble the mechanical Darth Vader we all know and love. He'll lose more of himself and become more and more machine. It is true - I'll tell you how he does that in one way tonight.
Here is what they had planned at the stage of involvement where I was at. Anakin loses his right leg after the fight - and yes, Anakin and Obi-Wan do battle it out in the lava environment we've dreamed about since the early days. More as I dare.