I had this feeling that this "Power" arc should be a movies because of its graphics or drawings but now with final episode now I am sure it was a movie which made but not released and now released as a filler arc there is a few points I noted :
1) In this arc Kabuto looks different.
2) Normally Naruto's filler consider time line and don't disturb it but here Naruto's nine tail mode is shown like Naruto don't know how to do that and his transformation into nine tail where in movies they messed up with time line as in this arc.
3) At the climax after closing song a little video shown of the same story then trailer of next episode something only you can note in movies.
Those were my points let me know what are your opinion.........