Some of this is kind of pre-mature.
1.) If Pein captures Naruto, and I don't think he will, then it's really annoying because it's already been done with Gaara. I don't believe that either will win in this first encounter other than Naruto forcing a retreat of Pein and Konan, not death. People say that Naruto won't use his full arsenal because of the danger to Konoha survivors, why can't he simply move the fight elsewhere? Gaara chose to fight in the Sand village, or he was stuck there by his fighting style.
2.) Do we really know much of Naruto's abilities since the time-skip and now his sage mode training? We saw him beat Kakashi because of Kakashi's new book from Jiraiya. Orochimaru was him in Kyuubi form 3-4 tails. Kakazu was a one-shot kill. All we see him do is train. The time-skip was training, teaching, and bonding. When he kills people, he tends to one-shot them because his jutsu are so powerful.
b.) Also, that frame with the person running with a big scroll on their back and maybe cape? It wasn't a Pein body, as mentioned by others, it was likely Naruto. I don't care if he has a cape, but I've been dying to see him with the scroll. I think that also may indicate that his summoning skills are significantly improved.
3.) I think Naruto can fight with Pa frog, but not in fusion, unless it's too dangerous for Pa frog. I think about that flea for Inuyasha. Also if he summons Gamabunta, Gamabunta knew how to fight Gaara and the Shuukaku. If there's a toad bigger than chief toad, than it's likely to also have immense experience. Right now Pein is pissed, which is why he blew up most of Konoha. When you're angry/emotions cloud you, you don't fight as well (i.e. past Naruto).
4.) I expect a much more calm and collected Naruto to return on a giant toad equal to or better than Gamabunta. Yes, seeing Konoha will upset him, but he'll recover. Then we will see a badass battle of Pein and Naruto. It's time for "god" to lose. Naruto has always protected Sakura, this time will not be any different. To me this is the Naruto vs. Gaara fight over again. They may beat the crap out of each other to the point that a Konoha ninja/s will rescue Naruto while Konan retrieves Pein assuming that's Nagato, and maybe if it isn't.
b.) I've been saying this for a while. Pein and Konan will lose, which will fracture their self-image (God and Angel of God). "How can God lose?" That's devastating. In theory Madara knew this, and it's why he sent Pein the way he did.
c.) I honestly don't think that Madara could've done the damage to Konoha and the ninja as well as gather information the way Pein was able to. I don't think the EMS is necessarily better than Rinnegan when we haven't seen Madara do anything other than use his space-time jutsu to dodge attacks.
5.) I hope Yamato is alive. Apparently the first Hokage used his Mokuton (wood) jutsu to build Konoha. I think that ANBU mention this during the 3rd fight Orochimaru. Yamato is going to be useful for this.
6.) I love Kakashi, but how the hell would he have survived that blast? Tsunade was at ground zero, but she can heal herself with that Mitotic regeneration jutsu. Danzou must be crapping his pants in his little fall out shelter. If the elders and Tsunade got wiped out, Danzou will take over. The only person to oppose him and ANBU root is Naruto and his crew, but they wouldn't back him as the Hokage, just to oppose Danzou.
Supplementary timeline of Naruto's fights and training:
1.) VoE: Sasuke
2.) time-skip: train
3.) Kakashi bell
4.) rescue Gaara: Oodama Rasengan (one-shot) after being in genjutsu
5.) make wind-element Rasengan
6.) One-shot Kakazu with FRS
7.) Sage-mode trainin: sage-mode, one incredible new technique, toad kung-fu, hermit technique/jutsu.
8.) Pein (1 body +/- Konan) fight ?
