This actually sounds more reasonable than Sasuke trying to unseal Orochimaru via the Sword of Totsuka. The Narutopedia article here on Cursed Seals ...
http://naruto.wikia.com/wiki/Cursed_Seal_of_Heaven
...says that Kabuto previously said before that the Cursed Seals were embedded with Orochimaru's chakra; therefore, it's more plausible that Sasuke will manipulate this chakra in Anko to communicate with Orochimaru.
I think Orochimaru will only be here for a short duration. I don't see much use for Orochimaru's character in the storyline after he explains this secret Suigetsu obtained from his laboratory.And last but not least do you guys think Orochimaru will have an extended stay? Or is this going to be a conversation, perhaps a small battle and then him dying again? Or will be be brought back in a way were fighting is out of the question to begin with. If I was sasuke I would bring Orochimaru back and put him in the body of a white zetsu then most chunin can beat him 1 on 1.