Chibi Nanao is indeed <3. Now I'm going to take a shower because I feel like a dirty old man after saying that.
I feel like an idiot for not even considering that Tousen would be involved in this arc. His Bankai to take out the group to sort out the incident with Kensei seems to completely make sense after reading chapter. wonder why I didn't think of that? >_<
there are things that still don't add up though. at the end of the SS arc when Aizen was escaping to HM, he stated that all of his experiments to create a "new being" (Vizard & Arrancar). If that's true then, he never saw through the end of this current experiment and doesn't know the existence of the Vizards that are residing in Karakura (well he might've learned of them when Shinji faced Grimmjaw).
still, there's still one string loose in this story: the Hougyoku. as of this chapter, there haven't been any hints pointing to it. oh well, next chapter, I'm hoping that it'll enter the picture.