So Susanoo is actually the armor itself, that is a relief, I guess my worries about this concept were unwarranted. Judging by Itachi's 2 blind eyes it looks like Susanoo is a Mangekyou ability and at the last minute Itachi used it creating this impenetrable armor. I had my doubts about Susanoo being a taijutsu but now that seems to be likely considering the look of it and the fact that Itachi implies that its more than just a shield. I don't really see how the battle could go much farther now though but I am guessing Orochimaru will factor in to what happens next. Sasuke's left eye now looks like Orochimaru's so I am sure there is some significance to that.
Overall this chapter definitely exceeded my expectations, hopefully the conclusion will be cool. Itachi seems to be blind now but he looks to be doing pretty good otherwise back to being calm and in control. I am not going to call a victory for anyone yet though especially since this has been so back and forth.