Maybe it is another rasengan, but i don"t it to be, cause there are to many rasengans. And about Danzo, well maybe he is hellping the akatsuki. Remember what J-man said to Tsunade, that she should be careful of ROOTS. Or maybe he is trying to protect Naruto. Well, we will see later. And I think that Kishi is doing this cause he wants Naruto to come later.