I didn't see the dual-wielding thing coming, but it does make sense contrary to what people are saying. One sword represents the hollow and the other Zangetsu, each having their own ability no doubt. Kyoraku whom dual wields zanpakuto has even told that each of his swords represent a different "person"(as well as ability), same goes for Ukitake.
I'm excited to see his bankai though, curious to see if it will be some sort of fusion or what between the swords.
Overall, cool chapter.