Good insight! LogicGreat chapter. I knew Orochimaru was coming back, I just didn't expect it to be so soon. I'm sort of glad Kishi isn't wasting any time progressing the story, when he wasted (in my opinion) so many chapters talking about Kabuto's childhood and a few other things recently. Last chapter progressed a few other issues a little bit too (Madara is "done" playing, and wants to look for the kyuubi, Tobi is resurrecting an incomplete 10-tails). This chapter really pushes forward Sasuke's story arc a little bit and brought back Orochimaru, a fan favorite.
It opens the idea that Orochimaru had and was able to use senjutsu chakra. I thought Kabuto said that Orochimaru wasn't able to use Senjutsu, because he didn't have a body able to handle it. This does explain why Orochimaru's eyes had black areas around them and why they looked like a snake. Orochimaru's eyes look almost exactly like Kabuto's when he was in full "dragon" mode. I'm just wondering, did Kabuto not know that Orochimaru was able to use senjutsu, or is Orochimaru really not able to use it to the same level as Kabuto can now? Re-read chapter 579 where Kabuto says that Orochimaru didn't have a body able to handle senjutsu, and that Kabuto had surpassed Orochimaru in its use.
I also find it kind of interesting that Kabuto didn't try to resurrect Orochimaru. Kabuto clearly had all the necessary parts to do it. Did Kabuto not know it was possible? Maybe not. Sasuke knew that Orochimaru could come out of the cursed seal because he had seen it happen before, but Kabuto hadn't witnessed the battle between Sasuke and Itachi and might not have know. Kabuto did know a heck of a lot about the cursed seals, however. I wonder why he didn't figure it out.
In this chapter, Suigetsu does seem to make a distinction between "Orochimaru" and "The man who knows everything." In the last chapter, depending on which translation you read, it seemed like Sasuke was talking about them as the same person. Now, it doesn't look like that.
Sasuke seems to think that Orochimaru is the only person able to use the power in that scroll. However, Suigetsu seems to think it's something Sasuke could do now, or with some training.
When Sasuke shows Orochimaru the scroll, Orochimaru asks "What do you want to meet them for?" That suggests that the scroll has something to do with some other people. Maybe it's a way to summon people. Maybe it's a way to enter into a secret or hidden place where certain people live. Maybe it's yet another technique to summon the souls of the dead (or, transport a living person to the realm of the dead). Maybe the scroll contains the secret to Edo Tensei (which neither Sasuke nor Suigetsu knew, previously).
Orochimaru also seems much more...calm and less violent and angry than he had been in the past. He seems to accept Sasuke's character development, and even seems sympathetic towards it. He does claim to want to steal Sasuke's body still, but he doesn't seem as aggressive or selfish about it as he used to.
It's entirely possible that, after everything we've learned, that Orochimaru was not entirely a "bad guy" like he appeared. Danzo was kind of a jerk but he did jerky things because he wanted to protect the village. Itachi slaughtered an entire clan AND joined Akatsuki, but did those things to protect the village. It's possible that Orochimaru did the same kinds of things: He did the kinds of dark, evil medical research that was necessary but couldn't be done in the village. He helped Danzo. He opposed Akatsuki (after joining it and then quitting). His invasion of Konoha is the only real reason I would say this is not true, but if he used it as an excuse to put a more powerful hokage in place (Danzo or himself) there's some justification in it. Also, attacking the village would force them to defend themselves and made the village stronger, which in some way of thinking is a good thing.
This chapter was extremely interesting on a number of levels. I gave it 5 stars, and am looking forward to seeing how this story arc progresses.