Agreed.
I've seen a lot of people saying things about how Naruto shouldn't be able to counter the combined Bijuu-Dama with just a single Bijuu-Dama...
Now, my memory isn't perfect, but I seem to recall that Kishi mentioned somewhere much earlier on that the kyuubi is the most powerful of the tailed beasts by a long way. Something about how each tail multiplies the base power, or the more tails, the stronger they are, but in an exponential fashion (so Karuma would be many times as strong as the eight-tails). I'm currently looking back for confirmation on this, but that seems to be the logic behind Naruto trying to counter the combined Bijuu-Dama in a single go.
The other thing was that people were asking about where the cape came from... and this had already been answered. The chakra cloak that surrounded Naruto in kyuubi form simply split down the front, forming the cape, from which (I assume, since it isn't shown directly) the rest of the chakra streamed, forming Naruto's Bijuu Mode.
Anyway, logic and stuff aside, this chapter was epic, and I think Naruto will continually improve his bijuu mode until it's more like a physical apparition than a pure chakra one (like the eight-tails)... This would require a more "perfect" joining of Naruto's and Kurama's chakras... which should be no problem.
As to what happens to Sasuke, I'd suspect that he finds a new way to use EMS, or obtains Rinnegan and finds a new way to use it, etc. As far as eye techniques go, he basically needs to use them in a way we've not seen before, or he needs a new "eye" entirely in order to keep pace with Naruto's insane power.
Of course, I suppose there's the chance Tobi will successfully retreat with all (or most) of the bijuu and then seal them into Sasuke, who'll then use EMS to control them.
That's as far as I can see...
That, or Naruto will continue to get a power up and use Sage Mode to perfect the bijuu transformation (I think this to be more likely than combining the modes), since Sage Mode is just extreme concentration... possibly somehow recombining the tailed beasts into the Juubi once more? Although that perhaps is suicide at this point -- he'd want to make sure they all were "friendly" like Karuma and the eight-tails before combining them into something with that much power.