Yay for overreactions.
Itachi said he gave Naruto something to protect him against Sasuke. One possibility is Susanoo, Itachi's third Mangekyo ability since it seems to be the ultimate defense. Or something along those lines...
On this actual episode: Killing everyone and going through death sequences for them only to bring them back is stupid and cheapens any death here on out, yay for that. I like Kakashi but am not really excited to see everything returned to normal.